Maybe this would work for simple websites. But for web apps, it's a hard pass for me. For context, I write a web-based POS application, and waiting for a network request on every micro interaction is a no-go.

There are lots of other problems with this approach that could be solved, but aren't immediately obvious, such as (similar to React) over-rendering. If someone has their focus in an input within the frame that gets swapped out, they're going to lose their focus. This has implications for accessibility as well as just regular usability.