There's trails for bikes of all types at Mammoth. You may be able to ride about 80% of the park relatively comfortably with it, as long as you ride to the bike's limits and you yourself aren't the bike's main limiting factor. A trail with a single jump apparently qualifies for double black diamond, so don't get scared away by that designation.
I did mammoth with a 100mm XC 29er. My favorite run was "Off the Top", hop onto "kamikaze", take lower "shock treatment" to "richter", and do that optional hill at the end. Only did the other side to explore each fork once, where Brake Through goes to Paper Route ends up, since they shuttled you back to the main lift from there, but did Flow a few times including the drops, and also did lower Twilight zone doing the jumps practically blind (first time, without scouting the landing). The other times I did upper twilight, I just skipped the lower part and rode back towards the main lifts.
There were a few trails that gave my bike trouble like Upper Shock Treatment, mainly due to a couple areas that could lead to endos if you go too slow. Actually passed by someone who busted their collarbone there at the last turn on it on that one, so I think many people have trouble on that. I shied away from Techno rocks, since it has a sketchy entrance to the drop, and of course I skipped that optional drop off the side on the way to twilight zone (I'd do techno rocks before that one). Jill's Jumps... didn't even try to ride it, but the guys waiting at the lifts were talking about how the bottom drops are exposed and sketchy if they get caught by a gust mid-air. I had trouble on my 29er clearing the tables on Recoil as it had some odd rhythm I couldn't get down from short to long to short again, etc. and I kept losing speed casing them, so I wasn't attracted to the notion of hitting bigger air jumps.
You can technically ride everything there, if you have decent skill. Those tires are super sufficient; I went with less, but of course I wasn't trying to race. There's plenty there that you can ride to work your way up to bigger stuff, building confidence. Perhaps hook up with a vet that knows just how hard the the trails are and will choose which to test your skill on.
Mine's the one way on the right. Buddies are on matching Enduro (26).
Buddies getting psyched up at the top.
Moving on after checking up on the guy with the broken collarbone, on Shock Treatment.