The big thing with burnout is that dealing with it well really comes down to being prepared and knowing that it exists. A lot of people who have really catastrophic burnout don't really know what it is until they have a moment half-way down the path where they're like "Ah, I'm burning out" but at that point a lot of the remedies are a little too late.
Yeah, MMO burnout is real too. I actually thought about talking about it for a while; I've never been much of an MMO player, and I tend not to play any one thing for a particularly long time, so I'm not as familiar with it first-hand, but it's a similarly big issue.
The funny thing is that I've pretty much always tinkered with my own systems (I was introduced to tabletop roleplaying by 1km1kt, which is a hobbyist community dedicated to making free games), but it wasn't until I started having to deal with burnout that my games became decent. It's not a destructive, entropic experience necessarily, but rather something that's just part of the package, like soreness after you exercise too hard.