you can get a full carbon "big mountain" bike with GX for $6k from transition and rocky.
really nobody needs more bike than that, and you only even need that much bike if you are in the top level of mtb riders, and ride multiple times a week to keep your skills up.
for an average singletrack trail rider, you'll never run into the limitations of a $2000 bike, but if you have gnarly rocky trails in your area you might spend a bit more on better suspension.
