Every day I go to work as a glorious customer service rep I get the joy of reading old people's paperwork in messy, unreadable cursive. Granted no one should ever write in cursive on an official form, but it's really hard for me not to pick it out as my first example having been at this job for a while now, and before that did a stint as a office jockey for a few months in the military making sure forms that went to the Squadron Commander were up to snuff.
The way it is taught in school is absurd. We teach children to print and attempt to get them to write legibly for the first few years. Which in itself is very hard especially for a right dominant kid who's brain decided it wanted to write with it's left hand, I don't know why ask my childhood. Then soon after, second grade for me, we start teaching cursive which is even more difficult and honestly I was never able to write anywhere neat enough to let someone read besides a grade school teacher who is practiced at pretending to know what she is looking at. Quickly after that, which now is even earlier watching my nieces go through school, we teach them how to type. These children are already practiced at this now too, not playing Oregon Trail for 2 years while going down to typing town where learning's lots of fun. My nephew of 4 can work an iPad better than my father and not hunt-and-peck either.
Signatures are a poor argument. That squiggle isn't mine! Look at the rest of my squiggles see they don't match up. If you are worried about identity theft a signature isn't going to stop it. If that was your last resort for preventing it you are way past screwed already. Hell, I have "SEE ID" written in block lettering on my debit card and that has only been acknowledged maybe 10 times in the 4 years I've been putting that on it. When I'm at Best Buy I put a straight line across the pad because those digital pads are even worse, and no one bats an eye.
The only legitimate point in my opinion is for people who claim it can be faster and more efficient for note taking or personal righting. In which case no one else sees it nor ever should. So if it interests you that much go learn it as a side hobby if you can't short hand or type quick enough to write something down.
So until this day comes, which it will. Every time I get something I have to read in cursive I really just want to: