Good point. I didn't even look at the picture. When I change a chain, it's because the teeth are mostly gone from getting dull, and being sharpened. The cutter can get down close to about 1/8 to 3/16's long.
If you're going to run a chain saw, you need to know how to sharpen a chain. I sharpen at least every couple of tanks of fuel. It's much easier on your arm if each tooth needs 2 or 3 strokes of the file, than if it gets dull enough to need 7. That chain probably needs 7 strokes per tooth. Any time someone, including some who run a saw for a living, their chain is dull enough to need 6 or 7 strokes per tooth. It always amazes me how many people, who run a saw for part of their living, aren't so good at sharpening a chain.
A sharp chain is much easier on the operator too. You have to fight a dull chain, and it's hard on the saw too. I try to never let the chain hit the ground, but if it does, the chain gets whetted the next fill up.
I learned how to sharpen a chain, before I ever tried to sharpen a handsaw. The feel for the file learned on a chain made the switch to a handsaw pretty easy.
If you are right handed, sharpen the right cutters first. If the left cutters are sharp, and your hand slips sharpening the right cutters, it's Very easy to slice a knuckle.
On a chain, you push straight back into the curve of the cutter, as opposed to sharpening a handsaw where you mostly push down. Tighten the chain first, before sharpening it.
If you have to take one somewhere else to get it sharpened, you might as well not bother running a saw. Even the guys that ask me to sharpen their saws, who run one for their living, try to sharpen themselves, but just aren't so good at it. They usually get the angle different on each side, and get the cutters different lengths. The Stihl chains have a little indicator groove on each tooth, that shows you the angle.
After several sharpenings, the depth gauges need to be lowered. There are gauges for different depths, that sit on the chain, and limit the depth a file can cut them down. They make special depth gauge flat files, with no teeth on the edges, so they won't cut the cutting edge of a tooth.
That .043 gauge chain takes a 5/32" round file. Depth gauge clearance is .025.
Here's a video of me running a hot rodded 92 cc saw. The 180, which I also have a stock one of, is a 32cc saw. This saw in the video is pulling a 10 tooth sprocket. The chain is a well used Oregon 72EXL, with the depth gauges lowered to .035. I don't push one hard. Just clearing some blow down trees off our trails. This was a 10, or 11 inch Silver Maple. A little embarrassed with the chain pinch, and no tan at the end of Winter.
https://www.youtube.com/watch?v=R2cdN53BxGs
I didn't know what we were going to run into that day, so I took the 180, and the 066. The pile of brush you see at the first of that video is the limbs cut off that tree with the 180. It's a nice little limbing saw. The old WRX makes a fun farm vehicle.