Everyone loves to complain about how bloated Electron is. No one offers a solution that performs as well in supporting all of modern webs technologies.
So some of the richest companies in the world chose to invest in the more powerful platforms, does that mean if you don't already have billions in the bank, you aren't allowed to create applications for users on multiple platforms? It is an enormous amount of work to learn the intricacies of multiple programming languages and frameworks and then to get feature parity accross all your native applications will literally take you like 3x more effort to implement them. Moreover, the reason these companies chose native is because it provides more features and the reason web technologies can't provide these features isn't technical, it's political.
A smaller company’s ability to compete is not my problem. But why would I want to give any random web page that I browse to the same access to my computer or phone that I give an app that I choose to download that is much better sandboxed?
And most apps that would be suitable for PWAs are in fact free. How would Apple or Google benefit financially?
Besides most of the App Stores’s revenue comes from games
What happens when either Apple or Google introduce a new feature to their native platform?
Nope, the product managers in the tech industry do. It's all about cost (or perceived cost). Web tech is more successful because it seems cheaper. Not because the resulting apps are better.
revenue-per-employee has been at record highs in the industry for years now. Maybe companies could hire a couple more devs to make decent user experiences and native apps, instead of cheapening out and treating development like a cost center and using Electron apps as a way to just hire fewer devs (at the expense of a worse user experience).