Your claim here is that a browser vendor could somehow fork the DNS and use its own .COM? Explain how that could possibly work.
Lets say .com gets mismanaged. Community is infurious. firefox/chrome/etc demands that . remap .com to new more trustable entity. If . does not. firefox/chrome/etc then remap . to new more trustable entity, because .com must be as trustable as ., because .com is that important. New . give back ownership of all tlds to their previous owners. Except for .com. .com goes to the more trustable entity as intended. New .com then does again similar import of all good xxx.com.
In this whole incident, no one loses the ownership of their names except for .com and possibly . .
Now no gov can touch *.com. Though its different for cctld. Those are owned by their respective govs. Same goes for gtld. But no one gets to mess with . .com .org .net.
Ultimately its about deciding who gets to own "x.y.z" string brand globally/contextlessly. World obviously need a single naming system. Either that or expect to have multiple owners to "google.com".
My suggestions are required otherwise why would someone build a global brand if ownership is not safe or guarnteed enough. Future is way more chaotic. Without crypto, a global naming system is not going to survive.