In order to fix some other unrelated issue I wanted to run chrome as sudo. The Terminal output told me to run the above-mentioned command. Besides that not being helpful I get an error "Cannot open profile" and some other things each time I open chrome, even via the graphical icon or a plain google-chrome in the terminal. How can I reverse this?
So in the post @steeldriver linked (in comments) I found the solution:
Assuming there are no files in your home directory that you want to be owned by any other user or that you want to have any other group membership (for sharing), you can run:
sudo chown -R $USER:$USER ~
If you have any files where you need to preserve the group owner, you can run
sudo chown -R $USER ~
Credits - (user Eliah Kagan)
I didn't need the latter, but now everything is fine again.