Apache. And winget-cli is licensed under the MIT license. So although the licenses are incompatible, the end result would have been the same even if Microsoft had simply forked winget with the Apache license, although in that case they would have had to credit the original author, and the lack of credit is the original author's main issue with how this was handled.
Seemed to me we need some carefully worded clause that help provide some compensation if something like this happens.
But M$ should be ashamed of themselves for not at least offering some compensation.