@Tutanota Kinda good. Kinda bad (perhaps).
Allowing Tutanota users to register accounts stops or makes it unclear for people to realise Microsoft is not good in long term and in the longterm we need to have our own ways or just have it away from more-corporate / BigTech way$... which is not aligned with your ways also I believe.
So being blocked fro your users registering actually set that alignment correctly and the message was clear. One of the only reasons to allow it / undo block is probably it's more profitable for them or good for research on your efforts.
(it's when they allow us to 'use them' I feel it's worse in the longterm)