Though I haven't played this game long, (my hours are on Xbox, not steam, I just happen to own it on here) I've found an amazingly engaging game that doesn't exclude new players.
When starting out, you're given the basics for every class. All the default weapons. As you progress, you'll be able to complete missions to get new weapons, though these new weapons aren't often better or worse than the defaults, just different, and it really adds variety and replay-ability to the game, without there being a set-in-stone meta. This makes it especially easy for brand-new players to get to grips with the game without feeling they're at a disadvantage.

I found it pretty easy to get to grips with this game within my first 5-10 missions, figuring out how I like to play and how to play my role in the team. Again, the fact that your weapons aren't amazingly disadvantaged over your potentially older, more experienced team-mates' weapons helps you feel as if you're actually being effective, and not just letting them do all the work whilst you pelt the enemies with a pea-shooter (I'm looking at you, Borderlands).
The whole class dynamic works really well, and every role slots into place pretty much perfectly if played by the right person, which more often than not (surprisingly), is usually the case. Every classes utility solves a minor-but-noticeable problem, like the engineers platforms when you cant climb up an especially steep ledge, or the scouts flare gun for lighting up entire rooms with ease. Things you'd never know you wanted in other games like this, but appreciate.

The replay-ability is huge. Every time you start a mission, the cave you're in is procedurally generated from an inventory of small, pre-made areas, all sewn together perfectly to create a unique environment. Once you're 30-40 missions in, you'll start vaguely recognising certain areas, as you've likely seen them before, however this doesn't happen often as there's enough variety in the pre-made areas to stop this from happening much. Every biome has unique materials, enemies, and geography, which is fascinating. Many games would simply change up some colours and assets and call it a brand new biome, but these devs decided to take it one step further and design unique underground landscapes to fit each biome.

As far as multiplayer goes, this is possibly the most fun I've had with friends since I was a kid. Joining a discord call, hopping into the game, starting up a mission and getting up to all sorts of ♥♥♥♥♥♥♥♥♥. When you're playing with good friends, the main mission is nowhere near as important as your friend who found out you can make your dwarf say 'mushroom', prompting the entire team to start chanting it until mission control tells you to shut the ♥♥♥♥ up, and ya'll scurry off to do whatever you need to do, still laughing under your breath.
Little details like these are what makes a game so fun, so engaging, so charming. Not the graphics, the setting, the weapons, the maps, all the new stuff being added in an attempt to keep a game 'fresh'. Sure, these things are still important. But what really makes a game worth playing is the little things. The memorable moments that make you wonder how many other people have had a moment like that. The fun little easter eggs and details that stick with you and make you laugh, the completely unnecessary but amazing mechanics. Its what adds soul to any game. And this game has soul by the bucketloads.

Worthwhile game, honest 10/10. Play it, you wont regret it.

Though I haven't played this game long, (my hours are on Xbox, not steam, I just happen to own it on here) I've found an amazingly engaging game that doesn't exclude new players. When starting out, you're given the basics for every class. All the default weapons. As you progress, you'll be able to complete missions to get new weapons, though these new weapons aren't often better or worse than the defaults, just different, and it really adds variety and replay-ability to the game, without there being a set-in-stone meta. This makes it especially easy for brand-new players to get to grips with the game without feeling they're at a disadvantage. I found it pretty easy to get to grips with this game within my first 5-10 missions, figuring out how I like to play and how to play my role in the team. Again, the fact that your weapons aren't amazingly disadvantaged over your potentially older, more experienced team-mates' weapons helps you feel as if you're actually being effective, and not just letting them do all the work whilst you pelt the enemies with a pea-shooter (I'm looking at you, Borderlands). The whole class dynamic works really well, and every role slots into place pretty much perfectly if played by the right person, which more often than not (surprisingly), is usually the case. Every classes utility solves a minor-but-noticeable problem, like the engineers platforms when you cant climb up an especially steep ledge, or the scouts flare gun for lighting up entire rooms with ease. Things you'd never know you wanted in other games like this, but appreciate. The replay-ability is huge. Every time you start a mission, the cave you're in is procedurally generated from an inventory of small, pre-made areas, all sewn together perfectly to create a unique environment. Once you're 30-40 missions in, you'll start vaguely recognising certain areas, as you've likely seen them before, however this doesn't happen often as there's enough variety in the pre-made areas to stop this from happening much. Every biome has unique materials, enemies, and geography, which is fascinating. Many games would simply change up some colours and assets and call it a brand new biome, but these devs decided to take it one step further and design unique underground landscapes to fit each biome. As far as multiplayer goes, this is possibly the most fun I've had with friends since I was a kid. Joining a discord call, hopping into the game, starting up a mission and getting up to all sorts of dumb shit. When you're playing with good friends, the main mission is nowhere near as important as your friend who found out you can make your dwarf say 'mushroom', prompting the entire team to start chanting it until mission control tells you to shut the fuck up, and ya'll scurry off to do whatever you need to do, still laughing under your breath. Little details like these are what makes a game so fun, so engaging, so charming. Not the graphics, the setting, the weapons, the maps, all the new stuff being added in an attempt to keep a game 'fresh'. Sure, these things are still important. But what really makes a game worth playing is the little things. The memorable moments that make you wonder how many other people have had a moment like that. The fun little easter eggs and details that stick with you and make you laugh, the completely unnecessary but amazing mechanics. Its what adds soul to any game. And this game has soul by the bucketloads. Worthwhile game, honest 10/10. Play it, you wont regret it.