[redserk]

Managing a public authentication service requires ongoing maintenance and monitoring costs. While they could pay a third party to manage it for them, this is a reasonable decision for them to keep costs low.

It doesn’t sound like Jitsi is sending Facebook and Microsoft transcriptions of your meetings so I don’t see why this is a big concern for a free service.

[layer8]

It requires you to have a Microsoft/Facebook/Google account in the first place.

[LightHugger]

Google/microsoft authentication is a platform risk and is basically saying those third parties own all your users. It can and does backfire all the time.