These are as old as mankind itself. All major religions are essentially meme-conglomerates. 'Music to invade Poland to' is a memetic concept, so is the dies-irae-theme in all music since the 1400s. Memes itself are 'sodgy narratives, and dinosaur-like news, history, or novels (hell, novels are meme-machines - they have sprung everyhing from quintessential fantasy races to actual mythofascist-occult ideas to bona fide suicide waves).
I'd argue that behaviours/media/ideas eventually need to be at least explainable to a significant part of a culture to become memes. You can explain 'Courage Wolf' to a completely uninitiated person of average intelligence in 30 seconds. You can explain 'Trollface' in a minute (with the whole cast in two more).
Skibidi Toilet escapes such explanations and is thus not, IMHO, a meme format. It's viral, not memetic, it spreads, but does not encode universally-understood meaning. There's no payload, just absurd emptiness.