Memes will be killed by some entrepreneuring copyright troll at some point.
In many jurisdictions, memes would either break the copyright laws or at least be in the grey zone. It's only a matter of time before someone exploits this. After one case, the platforms will ban them to avoid the risk of getting sued themselves. The same will probably happen for gaming videos.
The author of the dickbutt (if he/she can be found) might easily sell the rights to their creation to a copyright troll for one million dollars after which my scenario could take place.
You see, if they had the rights, we'd know who it is. You reserve your rights through registration. If we don't know, then there's no way to prove you have the rights.
In many jurisdictions, memes would either break the copyright laws or at least be in the grey zone. It's only a matter of time before someone exploits this. After one case, the platforms will ban them to avoid the risk of getting sued themselves. The same will probably happen for gaming videos.