Have you ever considered the fact that BIONICLE’s 10th anniversary was the first year since its inception that there were not BIONICLE sets?
I’ve never seen LEGO to really celebrate milestones for its original IPs. Brand-wide milestones, yes, notable years in its licenses (i.e. Star Wars) somewhat. But consider the 30th anniversary of LEGO space, one of the earliest and longest lasting “themes” that’s actually a concept lasting multiple themes, and we got a statue of a classic spaceman used as the macguffin of a Space Police III set. (And as far as I’m aware, nothing at all for the 40th.)