It's mostly that the game continues endlessly (with potential "victory" stopping points) and the larger game is trying to get more powerful faster than the game

It's mostly that the game continues endlessly (with potential "victory" stopping points) and the larger game is trying to get more powerful faster than the game gets harder. If you do its quite fun to accelerate in strength moving at absurd speeds, esp. in RoR2. It's a race, even though that's not super apparent up front. What makes it really hard is finding the balance of clearing a level (which stops enemies from spawning, which stops income) as a tradeoff for looking aimlessly for chests, and choosing when to move to the next level. Loosely speaking the meta is to progress very quickly up front because money and loot is easier to acquire in later stages. But I found that model to be kind of tiresome. They have an alt artifact mode where you don't need to open chests anymore and enemies just drop items instead. I found that to be a lot more fun and help even the playing field for playing co-op. It also encouraged sharing and teamwork in a weird way. When you have to pay for chests, the chest is "your" chest and you don't want to give an item to a teammate even if its better for them. When its a drop, sharing is caring. Your idle time looking for loot drops to zero and you can instead just play the game, go straight for bosses, and advance as fast as possible.