Back4blood doesn’t suck, but it did really take a while for the game to be tuned at the harder difficulties. It’s a solid upgrade over l4d2 in every way, but doesn’t benefit from nostalgia goggles. I wish it had l4d vs mode and mod support, but I still put in a hundred hours or so (haven’t checked dlc) which is pretty reasonable value.
The problem with back4blood is that it’s good: not great.

The “puzzle” is that when you enter the temple, it goes zero-g and a spinny thing in the middle pops up. You have to float to a thing that looks like a spinning top, and once you float through it, another one appears. You float through a dozen of them or so and then you get a space power. Such a colossal failure of game design that this was acceptable to have as any puzzle, but the audacity to make it literally the same puzzle at every other temple completely boggles my mind.
240 times. Sometimes a dude appears when you leave the temple, and he’ll shoot at you. There are better puzzles on the kids menu at Denny’s.
Upsides:
Downsides:

The problem is that loot is random, and it takes a lot of gear support to get to the point where a character isn’t getting hurt by fire, even with the relevant perk.
Cursed surfaces in general were just a massive pain, considering how precious Source was by default. Using a mod to get Source back on rest makes things a lot more reasonable, particularly in the first half of the game.

I’ve clocked roughly 80 hours across all the early access builds, and I’m confident that the game will do well in its niche based on what I’ve played so far. But it is a niche, and I don’t think any one game is going to change the market that much. It won’t flop, but I don’t think it’s going to make Larian the next cdpr
Of the first AGI is a companion app for this card game I’ll eat my hat