There really isn't anything in react that is inherently "bloated", most companies were indeed using it wrong, or at least in a naive way. Over-reliance on useEffects, re-render issues, non-memoized components etc. When used correctly, react 18 provides really fast web apps on whatever scale (small one pager app to massive enterprise apps).
> most companies were indeed using it wrong
If everyone is using react wrong, react has a design flaw. Other frameworks aren't slow by default.