People keep touting react etc but I swear every mobile ordering app I use lags like hell..

I don't doubt it. People make terrible websites with React.

However ... what might be happening is that you go to some websites, and some of them are great and others are terrible laggy garbage. When it's a bad one you open up devtools and see React, and that leads you to conclude that React is bad. But reality is that the good ones also use React, because most big websites use it.

Your reaction to the good ones is to assume they're well-built using whatever tech you happen to think is great (Rails, Vanilla JS, Vue, Svelte... whatever) but you're not actually looking. Hell, a great website isn't even a website, it's the experience of interacting with the business behind it. You don't even think about the tech when the website is actually usable.

Your reaction to the bad websites is to look under the hood, and you often find React.

That either means React websites are bad, or that React websites are good or bad, and it's not really React that's the issue. It's the team who built the site (and often not even the tech team; there's often some Product or commercial pressure that's driving the team to release something that's not really ready yet.)

Absolutely agree. I hate the state management mess in these frameworks.