So far I’ve just YOLO'd it. But if I install other software directly from git and the source isn’t fully reliable, I’ll usually at least check recent changes, or have codex take a look through the source, just like I read through PKGBUILDs when installing from AUR. It feels crazy that I then update LazyVim and suddenly pull in 150 new commits, some just minutes old, all with free access to my system.
If you manual update infrequently you are leaving a period for other people to get burned and flag issues before you pull the change, even if you don't look into a thing yourself.
If your update is the simplest version, a "git pull" -- then you're incorporating commits that have not "stewed" long enough for anyone to be burned. You might win the lucky ticket! (Saying this as someone who rarely updates nvim plugins, out of forgetfulness, not principle, and when they are updated I believe it IS a simple "git pull"...)
I mostly do, yes. There are exceptions for very mainstream and big plugins, but for the most part I do at least skim the new plugin code before committing it to my dotfiles repo. A nice thing about this ecosystem is for the most part, things don't change that quickly/often, and big refactors are quite rare