> I had so many issues with things getting silently dropped with no recourse (2FA codes, account recovery mails, etc.) on so many sites

This is not unique to Microsoft and really the source's problem — they did something to get blocked in the first place.

Add in the fact that you're almost certainly not the only one impacted, and that they have no interest in fixing it, it screams incompetence on the source's part.

Been there, done that, good luck explaining the problem to the app's first-level support in the Philippines because it's not in their script.

> and had Outlook forward to GMail

Till the day GMail hits you with the "We couldn't verify it's you" bullshit and locks you out of your account forever. Good luck getting support from Google, the word is not in their lexicon.