The browser has been a system-within-a-system for a long time now. That's a pretty big problem, because it's inefficient computation-wise and has very low interoperability with the host system, which has big implications. The user also has sort of an upside: the browser, being isolated on the host machine, is very portable. And, maybe safer, but I'd argue against this point, because a monolith is too hard to audit; if you want security and correctness you need many small components, not one huge one. But, those are user problems. Big vendors enjoy non-interoperability, because it lets them do user lock-in and have monopolies. That's also why we hardly have medium-sized vendors: only gigantic and minuscule.
If I had a magic wand,
- I'd make Web maximally interoperable, give an API to everything: look up Youtube recommendations or listen to Spotify programmatically or from the command line;
- introduce legislation to forbid non-interoperable for-profit (or infrastructure-level) software; otherwise businesses are incentivized to make walled gardens and lock-in users; e.g. no more countless chat apps;
- get rid of Javascript: it creates too many security and fingerprinting problems, and, if everything has an API, you don't need it;
- break up the browser into a composition of smallest independent components possible; it will get you `apt install facebook-local-events`;
- get rid of password-based authentication: what a horrible idea that was;
- get rid of any client-side possibility to track or fingerprint users; if you're making choices about what services to use or how, those choices can be fingerprinted, depending on some other things, but that's another matter; the other party should not be exposed to what hardware or software or configuration you use or how you use your peripherals;
- introduce consumer and competition protection laws to bring software out of the wild wild west in terms of legislation.
I've more or less described the destruction of Web as we know it, but also a creation of something much better, in my eyes. Doesn't sound very feasible, but that's what I'd do if I had a magic wand.