STAR and Ranked Robin are definitively not RCV.
RCV, or IRV as it's known elsewhere in the world, is an Ordinal voting system. That means spoiler effect and enforced two party dominance.
STAR and Ranked Robin are on the Cardinal side of things. No spoiler effect, because votes you can give equal support to multiple candidates.
If I really like two different candidates and don't particularly care which one wins, I can say that on a STAR or Ranked Robin ballot.
In RCV I have to make a strategic choice, and if I get that choice wrong, it's not just my guy who loses, but possibly my entire side.
So no, they are not the same. And it's worse because of RCV's lack of Monotonicity.
Non-negative responsiveness or monotonicity is a property of a social choice rule, which says that increasing a candidate's rank on some ballots should not cause them to lose (or vice versa, that decreasing a candidate's rank should not cause them to win).[1] This means rankings can be interpreted as ordering candidates from best to worst, with higher ranks corresponding to more support. Voting systems that violate non-negative responsiveness can be said to exhibit negative response,[2][3] perversity,[4] or an additional support paradox.[5]
And then explicitly;
Runoff-based voting systems such as ranked choice voting (RCV) are typically vulnerable to negative response. A notable example is the 2009 Burlington mayoral election, the United States' second instant-runoff election in the modern era, where Bob Kiss won the election as a result of 750 ballots ranking him in last place.[16] Another example is given by the 2022 Alaska at-large special election.
So no, RCV is actually somehow worse than First Past the Post.
Also, that rule about needing more than 50% of the vote? Yeah, that too is a lie. Ballot exhaustion means that it's 50% of the ballots that are left in the final round. If you didn't guess correctly who made it to the final round, your ballot is just thrown away. It's called ballot exhaustion.
Another popular lie is that your vote transfers in order on your ballot. It transfers in order to the candidates who are left. That's why Bob Kiss won from being ranked last on various ballots. The people before him were eliminated before the first name on the ballot, so the vote skipped a bunch of names and transferred from the first name to the last.
All this because when you hold an RCV election, what you're really doing is just holding a series of First Past the Post elections on the same ballot. You can't fix the problems of First Past the Post by repeating First Past the Post a bunch of times.