> One important piece of context is that Etsy currently has two major product stacks. For buyer-facing pages, we use PHP server-based rendering with jQuery/vanilla JS on the client to stitch things together. For our seller-facing pages and many of our internal tools, we use React-rendered SPAs with minimal server-based HTML rendering, receiving data from the same PHP server-side stack.
The unreasonable effectiveness of PHP
[EDIT] Just to add content to foster actual on-topic discussion —- is it likely that Etsy will be the only ones taking this off-ramp from React proper? Seems like the v15 -> v16 jump is onerous