It's hard to overstate how entrenched the app store paradigm has become. When you tell people "Hey, I released a new web app" the first thing they do is go to the App Store and type in the name. If the app doesn't show up there, they get confused and don't know where else to look.
Really, the only benefit of the App Store model is discovery – much more so than the claimed benefits of curation or security. The web offers an equal, if not better, security model – all web apps are sandboxed and must ask for permission to do anything. The browser sandbox is the most secure and well-tested sandbox in existence today. It has to be much better than native OS sandboxes alone since it can't lean on "curation" to keep outright malware off people's devices. The web sandbox keeps you safe even when you click a link to totally random website that hasn't been pre-checked by anyone.
The main issue is web apps just aren't discoverable right now. When you search Google, you get a lot of random stuff mixed in with web apps. I don't think consumers care what the underlying tech is – they just want solutions to their problems whether from a "PWA app" or a "native app". It's indistinguishable to consumers, except in discovery.