Most React applications do not end up like that in the real world. They turn into poorly architected over complicated nightmares, particularly on sprawling apps which is the reality in the corporate space. Not everyone is building hyper-focused single function tools which can be crammed in an SPA type framework. And the users suffer for this.
One of the finest turds I've seen recently is my electricity company's meter reading facility which is an over-engineered react interface for a single web form with two fields and a confirmation box. The whole thing pulls 590k down to do that and takes 5 seconds for the initial page load on an M1 MacBook Pro. That's the real end game for most people. The only reason it's like that is because the people who built it don't know how to do it any other way.
And lets be honest about Microsoft: they do everything from a front end or user interface perspective and randomly discontinue bad ideas about 5 years down the line. Like Silverlight, most of WPF, bits of ATL and MFC, an entire mobile phone platform that got rewritten. And their competing framework WinUI 3 doesn't even work properly. Their own O365 web platform is a fine example of where this turns into a buggy mess. I bet react is dead to them within 2 years on one of their schizophrenic switcharoos. The only reason they're into it now is to capture some market from Electron.