> everyone seemingly writing their own browser lately

Can you name/link to a few examples? I know about Ladybird:

https://github.com/LadybirdBrowser/ladybird/

but haven't noticed other initiatives.

> might be what ends up breaking their browser monopoly.

This post is a toy project, not a full-fledged browser engine, which is a large beast (even when you _don't_ do everything from scratch)