The impression I got from reading through some of the Windows Terminal[0] issues/release notes, is that
It's understandable that it's much slower and more challenging to make changes to functionality that's become part of Windows core.
If something in PowerToys turns out to be a bad idea, it can be removed. It's much harder to justify that when it's been baked into the OS.
[0] https://github.com/microsoft/terminal
