Regardless, it should be obvious to anybody that has ever worked in a massive corporation that a DIY approach with react will not be opted for. Talking about the corps where most people get jobs, not the ones that publish blog posts on hacker news
While it's public sector, I work for a fairly big, boring, enterprise org that doesn't publish anything on HN and for our apps that use a SPA framework, a “DIY approach with React” is pretty much exactly what we are doing,at least in my corner of the org. Never heard of anyone in the org using Angular (there's some shops doing jQuery/Bootstrap stuff, and some at least experimenting with Blazor which isn't surprising given how .NET-heavy the org has been.)
There was a time when Angular was sort of the enterprise Java of SPA frameworks, but I think that's kinda past already, and lots of big boring enterprises missed it completely.