Maybe this doesn't apply if you're an illustrator or a designer or something but: Never try to calibrate your computer monitor to have the correct gamma and white point and everything. It'll probably end up looking a little nicer by the end of it but I just don't think it's worth the struggle.

addendum

Writing this post with the on-screen keyboard because I'm repairing my laptop's hard drive so its keyboard is unavailable. I think there's definitely enough room here to display the last letter of these suggestion...

further advice/note to self

If you ever end up in a situation where you think that booting into MacOS recovery mode and running fsck_apfs will improve things, it's already too late.
(nothing bad happened, the disk just has exactly as much unremovable "used" space as it did before)

postscript

It may be meaningful in some way that the one common factor between all of these bizarre computer problems is myself. I plan to never learn.