Run a coil test just for that coil. Just to see how it look while firing.

This is most likely a sleeve (plastic tube) issue. If the sleeve is overly dirty or swollen, you'll get some binding.

I recommend removing the coil stop and replacing it as well since you'll already have things apart and (more likely than not have placed an order for other parts). Loosen things up by removing the two screws at the coil stop (on the right of your photo)

Slide the coil back and see if you can freely remove the sleeve from the coil's core. If not, you need to replace the sleeve AND the coil. If it slides out smoothly, then just replace the sleeve- don't bother to try cleaning it. It's cheap and should be replaced.

The pivot point is one of the few places that's recommended to be lubed in a pinball machine. That's probably why it got sluggish over the years as well, as the lube that was there from the factory (or other maintenance over the years....) got dirt ground into it and solidified it making it gummy.

It'll probably be ok in home use with no lube but if you have some, a small amount wouldn't hurt. (Not WD40... that's not lube). I assume that WD40 electronics cleaner is something different based on a very cursory google of it, it says its a cleaner that leaves no residue so it should be ok to clean stuff up in, usually for metal stuff I use isopropyl alcohol and teflon lube gel (just a touch... if you can see it, its too much).