IMO, the idea of trying to blur the line between client and server is a big mistake. I worked on WebSocket frameworks in the Node.js space so I was also tempted but I completely abandoned this approach years ago. Though with Node.js, I do often reuse utility functions between client and server, I reject any framework which tries to hide the separation. I demand to have complete understanding of where the code is executing and how. I need to know what is being executed, where and how.

I also avoid technologies where the code I write is different from the code being executed. This is why I've been avoiding TypeScript. It performs code transformations which obfuscate my understanding of the logic which will be executed. With TS, the code I write is not the code which gets executed. This is scary to me. My code gets compiled into some messy junk-looking code and then that messy junk gets executed in ways I don't fully comprehend.