They make it pretty easy to tell you what is and isn’t canon though. Anything made since Disney bought them and not under the non canon “legends” line is canon. With everything prior to Disney, other than the movies and the clone wars also going into “legends”.

Also then referencing older legends stuff in new stories is just implying that those stories in some way may also have happened in this version of Star wars. But they don’t make the old stuff canon, because they can’t be canon because all of the old stuff was an absolute mess and constantly contradicted each other. Which is why Disney did what they did.

I take the little easter eggs about legends as like “hey, we may adapt this story into the canon at some point with a new interpretation”