Sure, technically. But good luck getting anyone to use your version over the mass adopted one. And good luck fitting back in if they decide to take their fork in a direction you dont like, which isolates your instance further and further.

Other than writing the software that all of those instances use to stay up to date and in contact with each other, regardless of their federation status.

They are talking about the people developing lemmy, not some petty fight with the admins of one specific instance.

It kinda reads like lemmy.ml admins think images containing children are inherently pornographic.

Thats… Not a good look for the instance. Or its leaders.