If you made a browser run lisp, it would only be useful for web pages that are scripted with lisp. Most web sites are currently scripted in JavaScript. Adding lisp support to a browser is the easy part. It’s like deciding Latin is a better language then English, and then learning it. If you then came here and started using only Latin, it probably wouldn’t be very satisfying.
If no then why nobody has made it already?
If you made a browser run lisp, it would only be useful for web pages that are scripted with lisp. Most web sites are currently scripted in JavaScript. Adding lisp support to a browser is the easy part. It’s like deciding Latin is a better language then English, and then learning it. If you then came here and started using only Latin, it probably wouldn’t be very satisfying.