Its interesting that a lot of the design elements that WP had first have now found their way into Apple and Android. WP was not gash, but MS stupid decision making around development of apps meant a lot of top tier app makers stayed away from it. Thats what killed it.
I had 3 WP phones, all Lumia's from WP7 to WP10 and I loved them. The People hub app in WP7 was an absolute killer app, but the walled vendors like Facebook hated it because they couldn't push adds to it.
Its interesting that I went to MS Ignite in Amsterdam a few years ago and all the MS staff were using WP devices and this was after it had been discontinued. There is still a big following for WP on Reddit and Discord, people do love them, I did at the time.