it's not that it's harder to remove, with no reliable info about which commits are human made and which aren't, you can't reuse any of them from this point in time.

for the record, the diff just between 7.2 and 7.3-rc7 is over 1.5 million lines and comes out to a 61 megabyte patch. but linux has been accepting sloppy code for a bit now and the last clean version is 6.16.7.

you'd need a really well funded and motivated group of developers, and even then i worry how doable that is, especially if the goal is to stay linux-compatible.

Maintaining the kernel would be such a HUGE undertaking, and I imagine that's why nobody's done it yet. That said, we do know the last untainted version in case anybody wants to try...