I think my PS5 may have coil whine, but even while sitting beside it I can barely hear it. Not really an issue for me.
What DOES piss me off is fans spinning in rest mode. My PS5 fans are on while in rest mode when USB ports are powered. It's not THAT loud when I'm up, but it's super annoying when I am trying to sleep.
No drifting sticks, but I haven't played a whole lot on my PS5 yet. What IS concerning is my R2 is looser already than my L2.
Only PS5 games I played were astrobot and maybe an hour of Destruction All stars, so it's not the usage of adaptive triggers that messed it up. I was playing the PS4 version of Spiderman, and noticed it when I was about to 100% the game. It's a game where you naturally hold down R2, and by the time I was almost down with the game I noticed that when I focus and compare the two triggers, the L2 is indeed tighter, maybe by 5-10%. Considering I haven't used the controller much, and all I did was hold down R2 for it to already lose about 10% of its resistance, I'm very concerned with the trigger longevity.
As for rest mode, I haven't had any issues, but my console bugs the fuck out when I plug in a USB stick to transfer off gameplay clips. Whether it's in any of the USB A ports or the C port, it keeps thinking I'm trying to plug in a full extended storage harddrive, my disc drive says it has an incompatible disc in (even when there isn't anything in the disc drive) and I can't see my PS5's internal storage anymore. I have to unplug, reset to fix (and after boot it STILL tells me that I didn't power it off properly). I have an actual external SSD but I have no desire to test it out and brick my console.(EDIT: I used multiple USB drives as well. Though this was about a month ago, I haven't tried since).