On my 14 I installed the K&N cans so I can remove my OE air cleaner and still filter out some of the microns. When I inspected the OE element, I found eye size debris that the K&N could not capture, but the OE stopped it. So if I can see particles with the human eye, imagine what the piper will let thru.
Lets imagine that old movie called, 'the incredible shrinking man' and when he is in proportion with a boulder or a tiny spec of road debris, isn't that still a rock that can scratch things? So you now have this sharp object that is going to run a gouge down the cylinder and when the piston changes direction, this now releases the rock off the cylinder wall and can move past the piston, and down into the crankcase.
Here comes more microns that begin to scratch the cylinder finish. Add up all the lines and it begins to show an air gap or a place to escape so the compression is beginning to weaken, or where the bike has a shorter lifespan than if more protected by a tighter filter pleat.
If you are thinking of saving a few bucks by using a washable filter, a more breathable filter, then chances are, your bike is going to cost more to repair the cylinder wall finish, just so you have some compression built back in it.
There is a great marketing line that was true back then as it is now... "You can pay me now or pay me later..." for not listening to the turtle.
Tormenting the motorcycling community one post at a time