Apple makes sure that PWAs are a inferior experience on iOS. But they will always be at a performance disadvantage compared to native code on any OS because browsers are essentially their own operating systems and that comes with a lot of overhead. Fundamentally they have to do extra work to keep the host operating system safe from malicious websites whereas native code is assumed to be trusted. Kind of like trying to run a video game in VirtualBox, it just won’t run as smoothly.

Nostr is a pretty wasteful protocol in terms of resources which compounds the problem. But that’s not to say we can’t have fast Nostr PWAs. It’s just going to take more effort to get there.