Comment by seer

One thing that I found working in a bigger organisation is just how well React encapsulates Design Systems. You can have a dedicated team of talented frontend engineers that builds a really solid design system, and then other folks building the actual user facing bits can use them, and everything will be nice and consistent across all the various apps.

For example look at how well this has been going for Uber.

Now this is certainly possible, and even relatively easy to do in server side frameworks, but as others have stated, its harder to make sure it works nice in all the various edge cases and visual flair that is required for end users, and keeping it all consistent and upgradable across the board.

React (and I'd wager other component based approaches) shine there - its low level enough that you can implement anything with it, but still allow you to build complex things fast. And then are free to implement the actual business logic of the backend with the technologies of your choice. Even better various teams can do that in their preferred language, without the end user being affected by the difference.

Throw in react native to make the styles transferrable to mobile apps and you have the perfect sweet spot for largish tech companies. And since those tend to be the more vocal ones, we get this, in my opinion largely deserved desire to build SPAs.

Smaller teams / startups of coarse don't have those incentives, so they will understandably not have the same cost / benefit analysis.