I don’t think any of us need to be told how to mountain bike. But maybe you’ve been missing something. Do you fit the criteria and conform to all the necessities?
https://www.youtube.com/watch?v=WPVRU7jSYkQ
There isn’t just one kind of mountain biker out there, obviously. What does your clothing say about your riding style? Does nature and tree hugging form a part of your everyday? And how is your relationship fairing?
If I am on my 26 inch FS xc-ish machine riding up steep hills, and bombing down singletrack, getting some air ( using the term loosely here) having FUN, it makes my bike a AM bike??
I suppose these classifications have been created for the marketing peeps to be able to sell their bstest newest equipment.
Still does not stop me from riding my 100mm FS bike how and where I want.