I'm sure this was in the works well before Safari/iOS 11 implemented the majority of the PWA standard, but can someone help me understand what the target market

I'm sure this was in the works well before Safari/iOS 11 implemented the majority of the PWA standard, but can someone help me understand what the target market is for this in 2018? We just built a ground-up PWA and users LOVE it (Android/iOS, tablet/phone/PC). Why complicate and slow your programming + production software down by trying to XP?