Upcoming Windows 11 builds cannot install without internet and Microsoft Account

It's such an absurd lie. If Microsoft's idea of security is to force its users to authenticate online for a local account, they should never be allowed in the software industry at all. They're needlessly and dramatically increasing the attack surface of one of the most security critical software running on user devices.

And for what? Make number go up? If it's just another data collection scheme the at least I could understand why.

Because the NSA pays them to.

Why did they do to Skype what they did (first turn it from p2p to centralized and spyable and then just ignore it and let it die)?

Same reason.

(Opinions are my own, I have no inside knowledge.)

I vaguely remember hearing that P2P Skype was the bane of sysadmins' existence. Skype would elect clients on high-bandwidth networks as supernodes. This tended to be business customers - the very organizations MS wanted to attract. Skype's prodigious hole-punching ability made it difficult to throttle, so it got banned from a lot of enterprises. MS essentially hosted the supernodes on Azure, which centralized it.

As for encryption, on the other hand, Wikipedia says MS specifically added the ability to eavesdrop for law enforcement agencies, though apparently Skype had already added a backdoor for the NSA before MS bought them: https://news.softpedia.com/news/Skype-Provided-Backdoor-Acce...