Basically, Rey Palpatine at the end of Ryse of Skywalker, claims herself to be Rey Skywalker...Literally, she is saying to be a direct descendent of Luke Skywalker, the biggest known hero of the galaxy.
Disney basically was like: Lying is good as long you make sure no one can out you.
With Palpatine dead, the secret of her being tied to the worst man that ever lived is buried alived.
No one saw or knows exactly what went on down there on the planet, between her, Kylo and the fallen Emperor. Since she lied about her ID, we can assume she will probably lie again.
So the movie ends with a message that, IF you think it's ok to lie and you occupy a position that people won't even question you for, go ahead. Lie. Fuck it.
