Lego isn't Disney so not everything Disney does will appear in a Lego set. The popularity of the animated tv shows, I don't see as high enough for Lego to release a line of sets for. The most likely thing that might happen is sets based on TV shows through Lego Ideas. Overall, the TV shows just aren't popular enough for Lego to make a line of sets for.

Oh that’s too bad, because why haven’t they approved the mystery shack since they can make new molds now

May be profit related or be because they would have get permission from Disney, IP related ideas have less of a chance just due to the fact that they don't belong to Lego. Making it less of a possibility of being approved.

Oh 😔 but expected since Disney doesn’t know how to do business well

The majority of Disney-based Lego comes from films or classic shorts, like Mickey Mouse and Winnie the Pooh. Only in a couple of instances have we seen exceptions for TV series. Believe me, I would not say no to more DuckTales or to anything Darkwing Duck or TaleSpin.

Wasn’t there a cancelled Lego board game for Phineas and ferb