Same. We've been working on a huge React project for several years. Lots of graphs, 3d models etc ... and it is super-snappy. Only slow part is a WebGL-based chart component that visualizes 2-3 M rows of signal data. We can probably decimate the signal data to improve performance, but that has got nothing to do with us using React.

N.B. No one is using the app from their mobiles. iPad and computers only.

Our reasons for choosing React when there are so many alternatives: prior knowledge, ergonomics, easy onboarding, ecosystem.