I spend a lot of time worrying about this because I consult on accessibility issues, I an an accessibility advocate, and I am a low vision computer user.
Provided that developers use the proper HTML tags and ARIA roles, there shouldn't be any different issues here than with other JS libraries.
However, I want to stress that React, Ember, and Angular are amazing tools for apps, but if you are using them just to render static content, you're just inviting all kinds of accessibility issues that server-side rendering solved years ago. Web servers are optimized to serve static content quickly. Sending JSON to the client so the client can render HTML for a blog post or news article seems pretty wasteful, and again, invites accessibility issues that don't need to be there.