I’d say the expectation is that everyone sets their actual photo as their profile picture, that would probably solve your problem.
I'm almost willing to pay good money to someone who can explain how MS' user management works wrt belonging to multiple accounts/orgs/acive directories.
And regarding profile pictures, I’d say 10% of the people I interact with on zoom have them, and 0% of the people I interact with on teams. These platforms should get over themselves and realize people aren’t spending time customizing their profiles, because it’s just not important. You’re just a tool, zoom/teams. Try not to go wild with your fantasy of becoming a “virtual town square” that is integral to all aspects of life or whatever you are telling yourself internally. First goal is making meetings less of a pain in the ass.