At the $1000 level you can buy a complete hard tail mountain bike with no compromises of function or durability. Above that it just gets lighter and more clever, and $3000 will buy something really nice.
The present fad in trail bikes is 27.5x3" tires, slack angles, dropper seat post so you don't need to get off and undo the seat binder like the old days, 1x11 drive train. Marin Pine Mountain 2 is a good example, so is Specialized Fuse.
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Genesis 49:16-17