Well, in this case, the actual change is pointless, but also relatively harmless. If the user puts "split_lock_detect=" during install, then it just carries it forward into the installed environment.

It's frankly a bit weird that they assume a kernel argument during install would not carry over, except in select circumstances. I get it for parameters like "here's a kickstart file" or "here's the net configuration to boot with", which would be filtered out via a blacklist, but they have a whitelist and assume most parameters should be ignored.

But anyway, I can see someone looking at the code change, not recognizing why someone would want that argument, but shrug and say "sure, simple enough, it won't impact the vast majority of people and those that bother for whatever reason will just see it carried forward".