Probably an abundance of caution. I’m pretty sure referrer headers wouldn’t be sent if you modified the URL and that’s the only concern I can think of.

*For a new tab that is. Cookies aren’t going to care about a new tab unless you open a private one first.

Every. Fucking. Meeting. Why can’t teams just default to my system default.

They’re absolutely not doing everything they can. Everything they can would be to not use the works. They’re doing as much as they’re willing to do. If it wasn’t for the threat of lawsuits they wouldn’t even be doing that much.