The Terminal project was only announced 1 year ago[0]. As I understand it, they had to more or less split how the whole conhost.exe work in order to allow Terminal to even exist. The settings UI is far from sexy, but they're working on it[1]. I think it's impressive to know that 6 people did that in a year[2].
Regarding the slow startup of WSL2, yes it is slow to start, but would you rather have to wait 5x for a git clone command[3]? They even have a deep dive into how files are save in WSL1 which can be related to how it works in WSL2[4]
I completely disagree with the conclusion of performance is not Microsoft's concern. The comparison is to GNOME3 which was released in 2011. 9 years of development compared to 1 year. "The polish just isn't there"
[0]: https://devblogs.microsoft.com/commandline/introducing-windo...
[1]: https://github.com/microsoft/terminal/issues/1564
[2]: https://devblogs.microsoft.com/commandline/windows-terminal-...
[3]: https://devblogs.microsoft.com/commandline/announcing-wsl-2/
[4]: https://devblogs.microsoft.com/commandline/a-deep-dive-into-...