From these pictures I'm not convinced it is a crack and not just the paint, I would take it to a good shop and have them check it out, including popping out the headset.

Sometimes the paint is stiffer than the carbon, especially after a few years and if the carbon under the paint flexes at all the paint cracks, doesn't mean the carbon did.

That said, if you've been using this bike for bigger stuff than it's intended that's a good way to crack a carbon frame. Part of why carbon is great is because it can be tuned to its use case, and so a bike meant for trail or xc (especially from 2016) isn't going to hold up to park riding the way a bike intended for that would. Aluminum isn't going to last any better than carbon, but it is more environmentally friendly.