Why would anyone exhaust their time collectively spewing that Q is a LARP?

If ANYONE truly believed Q was a LARP they'd come to the conclusion and just leave without exhausting constant effort to say otherwise.

Why has this all of a sudden been the theme?

To all those following since the get go, don't lose faith, alright? Memetic Warfare is needed - the propaganda war must go on! If not for Q, do it against those we know are EVIL. Stand for what's right.