At the very least, Filoni introduced Novikov self-consistency principle-style time travel. Basically, it is time travel, but they can’t really alter the past. What happened, happened. The Prisoner of Azkaban is a really good example of this.
A part of me likes to think Filoni introduced time travel this way to Star Wars so “what happened, happened” are the canon rules and no future writers can write canon stories that change the past! Pretty clever I think.
Has the nu-Canon said anything about Anakin’s birth, etc?
Going by the “what happened, happened” rules of time travel, The saga’s grand finale could, if it wanted to, turn the whole I-IX story into a causality loop, hence the title The Rise of Skywalker.