If you wanted to pierce YOUR OWN TIRE for some reason, if you place a nail under a tire, (assuming you considered roll angle) it would pierce a tire quite nicely.
Rubber would seal pretty well to make it a slow leak, but cutting a channel into the side with an angle grinder or dremmel would help.
For maximum air leakage, take a 1/4in or 3/8 in steel pipe, then cut it into 4 in bars, then cut those bars in half with a diagonal cut. Place sharp end into tire groove.
Again, this is for educational purposes only if you wanted to get air out of your tire very quickly.
you can just pick up a bb sized pebble, unscrew the valve stem cover, drop the pebble into the cover and screw it back on. The tire will deflate with no damage over the next few minutes. Free, easy, nothing to connect you to it if you kneel down to tie your shoes between the cars....
On the windshield I’m totally okay with this type of vandalism. It cleans up easily with alcohol and everyone will know this guys a douche canoe until he can do it.
My only concern would be if the person was actually handicapped and the ramp was the closest spot for them...like I get that they shouldn't park there, but I'd excuse them in that case.
Which is a great reason to avoid being a douche in the first place, because there's bigger douches out there that do have some principles but love a chance to practice their doucheness on someone they determine deserving.