the fact that they work "sometimes" and "with the correct hardware/os" means you should avoid them, sorry
yet another reasonably good idea which was killed by the chicken-and-egg scenario between creators and supporters - even if Apple does a complete 180 and goes 100% pro-PWA, there will still be plenty of people out there with hardware which doesn't gel with PWA
forget it and move on - it was a good idea which needed 100% uptake to be a reliable avenue to follow, and it never got there, and won't because of greedy people who have their own agendas
PS: i'm old and grumpy and simply tired of fighting with people to focus on quality and reliability rather than profit - so now I just nod along