In my experience React is rarely the best solution and adds a huge amount of complexity which is often completely unnecessary because React is rarely needed.
In the early days my very controversial view was that frontend developers tend to be fairly mediocre developers, and this is why a lot of frontend frameworks suck and frontend developers just mindlessly adopt whatever the hot new technology is with seemingly no concern for performance, maintainability, security, etc.
But honestly I'm not sure this explains it anymore... There are a lot of really talented frontend development teams out there working for companies with plenty of cash to try something different. I don't really understand why there's no serious competitor frameworks in terms of market share out there.
As far as I'm aware there's no analogies to this in other areas of the web tech stack. There's plenty of backend frameworks to pick from depending on the product. There's also plenty of competitive DBMSs, cloud providers, package managers, code editors, etc, etc. I don't understand why frontend development is so static in comparison because it's certainly not that React is the perfect solution for everything.