To be fair, House's plots usually reiterated, "It's never Lupus."
(And the one time it actually was had a rather disappointing reveal, IMO)
I don't even need to read the article, the answer is more mouse bites
Lupus is kind of lousy for the punchy scientific format because it has as a nickname "The Great Imitator." (Note that the porphyrias are known as the "little imitator.") Because of this somewhat Protean nature, lupus can masquerade as quite a lot of things, leading it to be a casual element one would have to bring up and then eliminate in episode after episode. Thus, for screenwriting reasons, it needs a kind of general dismissal which would stick in the mind of viewers ...
but it was never lupus anyway. mostly.
It was Agatha, all along.
Time to bring it back for an special episode where House say's it's not lupus, but it turns out it is and they find out thanks to an intern, and then they cure it using this new therapy.
Maybe if one more painfully unfunny person repeats this tired joke that we see every time lupus is mentioned, it'll finally be funny. Let's find out!
To each their own. was a funny and nostalgic throwback. I haven't watched House in 15 years and haven't even seen it referenced since pre-pandemic.