For Python to work in the browser via WebAssembly you'd need to have python itself compiled and running to execute python. It would consume a lot of energy and

For Python to work in the browser via WebAssembly you'd need to have python itself compiled and running to execute python. It would consume a lot of energy and be much slower, I see no upsides. WebAssembly is meant to have lower level languages and programs run in the browser, not so Python devs do not have to learn a second language. Plus Python is not suited for event driven systems.