The 3b just has USB 2, so even with slow spinning rust, that’s going to be a bottleneck. But it’s probably still plenty fast as a remote storage device for media storage.
Edit: said I didn’t know OP’s use case but in re-reading they did say. Edited accordingly.
I love Linux, but I admit these are valid. I’ve had some of these same issues.
I haven’t had any issues with sleep on my devices, but I have in the recent past on previous hardware.
My WiFi doesn’t work at all on my desktop. Though it’s worked on a live image from another distro so seems likely to be an issue with the distro’s distributed kernel, not a Linux one. I run a rolling release distro so won’t be that the kernel is too old. But don’t care so haven’t troubleshot it much. My printer requires the use of vendor provided drivers, which are only available for some distros. It works, but not a solution I’m happy with. Never had touchpad issues.
I think package repos > collecting and installing your software piecemeal from all over the place. But having to deal with repos, flatpaks, appimages, etc. can be daunting.
Sounds like an OOM process kill maybe? That’ll show in your kernel logs if so. But no immediate visual feedback.
If there’s proprietary software that doesn’t run on Linux that someone wants/needs to run and there aren’t any viable alternatives then yeah, probably a non-starter. There’s wine of course but it can be a crapshoot. No shade intended towards the project. It’s amazing what it can do, even if it can’t do everything.