I don't think that's the case. I have the Earth View extension installed which shows a random google earth image.
I have this set as my homepage in Firefox as moz-extension://<extension-id>/index.html, and this has not changed since installing the extension. The page still works.
Doing it on restart makes the mitigation de facto useless. How often do you have 10, 20, 30d (or even longer) desktop uptime these days? And no one is regularly restarting their core applications when their desktop is still up.
There isn't enough energy in the solar system to count to 2^128. Now a uuid v4 number "only" has 2^122 bits of entropy. Regardless, you cannot realistically scan the uuid domain. It's not even a matter of Moore's law, it is a limitation of physics that will stand until computers are no longer made of matter.
