Loss of cursive is a big thing. It is just one more step in the brain and hand-eye development of every person and child.
It needs to be taught. Actually it needs to be taught before manuscript -- printing because it is easier.
A person writing cursive never takes their pen from the paper during the writing of a words, hence it is also faster than manuscript. Let's hope the teachers wake up and start teaching it again.
When using sensible letterforms, a semi-cursive style is faster than a detached style. Unfortunately, many schools have for years been teaching students to write "cursive" with letterforms that are hard to write quickly, and become illegible if written inaccurately. For example, the word "brick" is written by starting at the lower left, connecting the "b" to the "r" at mid-height, and connecting the "r" to the "i" at the baseline. The only place the "r" touches the baseline is at the right.
A more sensible style, as advocated by Kate Gladstone among others, would start the "b" at the top, exit it at the bottom, and then exit the "r" at the top (with a slight lift).
One thing that I blame for this is the amount of homework. There is so much, kids use computers just to get it all done in time. Also, assignments which are written are done in such a hurry to meet deadlines, the quality of penmanship inevitably deteriorates.