That's a lot of effort to avoid spending 79 cents on a new, two pole switch-- must just have been what the electrician had on the truck.

I see a couple potential problems here. The electrician (judging by the look of that switch, 20-30 years ago or more) stabbed the wires in the back of the switch to connect them. That's certainly easier than curling the end of the wire into a hook and screwing it to the side of the switch, which is why that method of connection exists, but it's also prone to failure over time. While it's possible your fan is broken, this connection is the likely failure point.

Second, he used the switch as a junction point by using both the backstab clamps AND the screws. Again, saves time, and also saves space in a crowded electrical box, but the proper way to have done this would have been to make a pigtail connecting the hot wire into the box with three individual hot wires-- one supplying each switch in the box.

I would replace the switch with a standard 2-pole, and any others that are "backstabbed," and use a pigtail to distribute power inside the box instead of chaining the switches together like this person did.

Or maybe your fan finally just gave up the ghost... In any event, you'll be correcting poor wiring practices.