Q: Why do states that don’t use RCV have RCV-enabled electronic voting machines...?
Because it is not only on the road map of the likes of the bastardly anti-American Marc Elias and his scumbag allies to enable Ranked Choice Voting, and it is their goal to have it become law in every state.
But having the functionality there allows them to exploit it, and if it is discovered, they can shrug their shoulders and say "There was a mistake in the software/configuration that caused this error. We promise to address it."
If it is discovered.
If it isn't discovered, it won't "be addressed" and will become part of the election results where vigilant people might not be present or sharp enough to be suspicious and pick it up.
“Q: Why do states that don’t use RCV have RCV-enabled electronic voting machines...?”
Personally I’m not a fan of ranked choice voting, if that is what you are referring to. But it does have some merits.