This is only true right now and only if browsers were not working to make more low level stuff available. There is very little limiting about being in a browser these days. Drivers, perhaps. Kernel stuff, perhaps.
But as far as a game is concerned? Or an email application? Or anything in the context of this discussion? Not too much limiting them.
It will always be true forever, or at least for as long as a web browser is a program run within an actual operating system.
It's not a competition. Pick the right tools for the job. If the job is getting your eMail or playing a relatively simple game, and a web browser abstracting as an OS can support your needs, knock yourself out.
If the job is something a bit bigger than that, use a more powerful OS.
Lets not try to limit the web, but try to make it better and then let the users decide which they would prefer to use.
Right tool for the job. That's all.
Browsers (especially mobile browsers) are unnecessarily limiting what can be done on the web. Adding additional permissions could enable browsers access to more system resources and components, especially on mobile.
Could you provide some examples of applications that don't require a lot of data that couldn't be run in a web-based environment, because of physical (and not current browser or software) limitations?
Google IO 2015, I believe, stores it's data so that when you load it up it loads from a cache that it's service worker will reload once you have it open. Allowing it to work offline and removing the cost of transfer at the beginning.
I believe, not 100% on that.