I'm not sure how much effort went into supporting PWAs for Windows Phone, I used to develop for that ecosystem during 8.x and the browser was a mess; cordova apps for WP required specific hacks to basic elements such as header, footer etc.
Besides, they where making good progress with supporting android apps in WP with 'Project Astoria' and iOS apps with 'Project islandwood'; both of those were pulled off abruptly. There was even a rumour in the WP community at that point that Project Astoria became too good that MS brass worried that native WP development may go extinct.
Btw, recently german WP enthusiasts managed to get Project Astoria working on several WP phones[1].
Besides, they where making good progress with supporting android apps in WP with 'Project Astoria' and iOS apps with 'Project islandwood'; both of those were pulled off abruptly. There was even a rumour in the WP community at that point that Project Astoria became too good that MS brass worried that native WP development may go extinct.
Btw, recently german WP enthusiasts managed to get Project Astoria working on several WP phones[1].
[1]https://windowsunited.de/so-koennt-ihr-jede-beliebige-androi...