There was a project announced this week that lets you write python scripts in HTML and have them execute in the browser (pyscript). Here's an example.
<body> Hello world! <br> This is the current date and time, as computed by Python: <py-script> from datetime import datetime now = datetime.now() now.strftime("%m/%d/%Y, %H:%M:%S") </py-script>
Under the covers, this uses pyodide and WebAssembly. This is one reason why I'm more excited about clientside WASM.
But what language will become the new lingua franca of the web?
It's no longer necessary to have a just-in-time compiled scripting language. Instead, you can ship binary blobs compiled down to WebAssembly from various languages.
Python in the browser has passed the prototype phase but will need a "compiled" form (If it can be compiled, it will be). Either some format like the PAR file or a webpack-like bundler system.