Funny

My documents has been the standard location for game saves for probably 20 years

1. It shouldn't be, especially since "My Saves" exists (or existed).
2. We're not talking about saves.

but that’s the reality and Microsoft KNOWS that’s the reality

Microsoft has NOTHING to do with where a developer decides his application will shit its data.

If appdata is really supposed to be for things like game logs, configuration and saves, can you explain to me why it’s hidden by default?

Because none of that is important for the user, unless they're troubleshooting. And if they're troubleshooting, they either know where to look already, or they're googling to find out anyway.

How is the average person supposed to copy saves? Back them up? Edit their configuration settings? This is exactly why my documents became the default.

Again, "My Saves", and we're not talking about saves.

personally have un-installed onedrive and had it break my file browser such that the onedrive button was still there and any time I accidentally clicked it the file browser froze

Don't know when you did that, but there was a time where OneDrive was "hard-coded" into Windows installations and brute-force killing it could break things. Which is why you didn't remove it fully, you just disabled it back then (log out, exit app, check if it's removed from Startup Applications, job done).

Nowadays you can uninstall it easily.

I don’t think you can chalk up every instance of onedrive slowing down a pc to user error, maybe some other software doing something unexpected + some user error.

Do you remember some 1-2 years ago when "debloating" was super popular? Like, every thread on r/Windows about new installations would have people shouting about the need to "debloat" by the use of some script from the Internet?

Do you also remember how that community didn't have a week without a couple "Windows Search is broken!!!!11" threads? You ever notice how the fad for "debloating" died down, these threads also disappeared?

So, yeah, I can absolutely attribute a bunch of obscure issues that were never acknowledged by MS to user error or "malicious" software.

I should be able to be the worst dev ever and do whatever “incorrect” things I want, regardless of what a software I never installed and can’t get rid of thinks.

Yeah, that's not how computers work.

It’s also just unexpected behavior, you’re telling me just writing to my documents will lag my pc?

No.

Or rather: "no, it's not supposed to".

I don't know what logs does Synapse, or whatever similar app, drop in the Documents folder. If it's thousands of operations per minute, there's possibly a chance that OneDrive would trip over and die over this. But having thousands of operations per minute saved in logs, in Documents, is just retarded design in the first place.

Let me put it this way: I develop relatively large scripts for work. I have them all in my OneDrive folder. I will also often unzip software packages into a OneDrive-synced folder. Thousands of files getting dropped out of an archive. I have never had any PC performance issues caused by OneDrive during that time.

And what if it’s pictures I absolutely do not want on Microsoft servers

Don't put them in a synced folder...?

Am I just required to know Microsoft put software that uploads it

Yes, you should know what you're doing on your computer. When you first open it, OneDrive tells you what the Status icons mean, so you should understand which folder is synced and which isn't.

without me ever consenting?

You logging in to OneDrive gave it consent to do the things it's designed to do. If you're fresh-installing Windows and use an MS account, you either get information about OneDrive during OOBE, or you get pop-ups about OneDrive after the installation is completed. Unless you just blindly close anything that isn't your Desktop, you are fully informed to the capabilities of your PC in terms of what OneDrive does and where it does it.