I have been a part of quite a few tech stack decisions at various companies and startups. I have literally never heard an argument made for react that included merits of the framework itself. The decision was always based on a combination for familiarity, ability to hire for eng roles, and the ecosystem.
Im not sure how this is a negative merit for React.
Besides if you are a small company, or a start up, your job is to get things done. Not to embark on a global technology crusade to push your favourite tech.
By and large the best thing about react is the overall ecosystem, libraries, talent and ubiquitousness. And thats a good thing.
It isn't necessarily a bad thing, but it doesn't align with the idea of how good react is or the technical merits of it.
I also am not saying teams I have been on that picked react made the wrong choice. That's all in context and as you said startups are often in the "get things done" mentality where tech debt won't matter if you can't survive long enough for it to matter.
We're talking about two different topics here. I agree, the ecosystem around react is huge and there are reasons a team would pick react. Ecosystem isn't an indicator of the technical merits of react itself though, and that's what I was originally responding to here.
Then why dont you pick jquery?
Its easy and well known, even now.
The answer I see is that react is technically good enough.
Using boring technology doesnt mean using the technically most advanced thing.
It means picking something safe and stable.