I'd be happy if those apps were asking to save to Documents like in the screenshot. But alas, reality is much more cruel. They always want to save to some vague OneDrive location, and won't even show you the local file browser without extra steps.
I don't want any of my files uploaded to OneDrive; therefore I don't want to save them in the OneDrive folder. I have other folders where I'd like to save my files instead.
So the behaviour I described is a persistent annoyance for me; despite you telling me it isn't a problem.
What I absolutely do not want, is my Desktop on One Drive. For starters, its often a scratch place. I don't want it instantly pushing 6GB of photos I just pulled off my camera's memory card to the cloud before I can sorr them.