For me it started crashing frequently as well. But I tried it on my windows partition with the same result (and even more frequent crashes). So I thought it must be some update of the game that introduced that and not Proton/Linux.

Then I tried several Proton versions and one of the older ones seems to be crashing less so I can actually play for some time.

I've seen other reports of this issue for nVidia cards; people are reporting that updating drivers helps, but it sounds like you've done that. If you're going as far as reinstalling the OS anyway, you might try out a rolling release distro; I've been enjoying Garuda quite a bit, and I've heard good things about Nobara and Endeavour.

I have almost the exact setup you have, except the RAM and I'm using heroic launcher. I have no issues with CP. My go to with game issues is to monitor the components in game. Install mangohud, configure the OSD to show CPU temps, gpu temps, clocks and also usage. That will help narrow down if the issue is hardware or software.

I had some weird issues with freezing and black screen and changing from Wayland to X11 fixed it.

My issue is frequent crashing/freezing, meaning I can’t play longer than a few minutes at a time

Could be overheating.

I use AMD hardware.

However, a few years back, I had a particular AMD card that, using its default onboard power profiles, tended to overheat with the default on-card power profiles in games which really exercised the thing; I understand that the vendor that made these cards had issues with insufficient thermal paste or the thermal paste detaching or something. That's the card vendor's fault -- the card shouldn't reach a point where it can get into trouble via overheating, but regardless, it was still a problem. Some people disassembled the thing and put more thermal paste on. I forced the thing to a more-conservative power profile, and that worked.

I haven't done this with Nvidia hardware, but it sounds like nvidia-smi can do this:

https://forum.level1techs.com/t/how-to-set-nvidia-gpu-power-limit-nvidia-smi/131467

Then to query your power limit:

sudo nvidia-smi -q -d POWER

And to set it

sudo nvidia-smi -pl (base power limit+11)

Might try restricting the power usage and see if your crashing stops.

EDIT: Might also try turning down in-game graphical settings. That'd decrease load and maybe also avoid any potential overheating issues, though it'd be a less-reliable option than the above, as you probably don't want to make your system freeze just by running some program that happens to throw a lot of load at your card. That also might avoid any issues that the drivers could have that the game is tickling. Worth a shot, at least from an experimentation standpoint, if you are looking for things to try.

EDIT2: If those do successfully address your problem and it looks like it's an overheating problem, you might also try figuring out whether you can improve the cooling situation on the hardware side, rather than sacrificing performance for stability.

Here's my suggestion.

First, check your RAM with Memtest86+ or similiar tool. This is the first test because failing memory can and will corrupt your whole system, and it's easy to test.

Second, if RAM is fine, check the logs. This is more effective then just guessing. Just copy-pasting possible errors to your favorite search engine usually points to the right direction. Archwiki has a nice tutorials about logs.

Third option is to test components one-by-one. Remove all unnecessary components, such as extra SSDs/HDDs, wifi cards, USB devices and PCIe cards. If it doesn't help, test your CPU and GPU by running dedicated CPU and GPU benchmark tools. If you still get hangs, try with another PSU. If your components test fine, it's likely a driver issue. See Arch wiki article on Nvidia troubleshooting for some tips about that.

Your last option is pure guessing. It's the most time and money consuming way to debug with the smallest chance of success, but still many people prefer it. Most often issues like these are GPU issues, so it's a good guess. However it's still a guess.

I hope this helps.

What kind of an error do you get when the game crashes if you start steam from the terminal?

The freezes and crashes could be caused by your nvidia card, I had the same issue before switching to amd

Try downclocking the ddr5 memory. If running at 6000 test it at 5600.