I was going to start another thread, but here works too.
Kids can get into pinball as long as you groom them into the hobby properly. If you have nieces and nephews who only occasionally play for 15 minutes on sporadic family gatherings, it'll be hard to hook them. But if you have a child who you can constantly teach technique, skills, and strategy they will slowly start to beat you as the years go on.
When my son was about 8 or 9 he had to write his first "chapter" book in elementary school. He wrote it about Gorgar. Fast forward to this fall, he just turned 13, he has an IFPA number, has played in leagues and tournies, and is a legit threat to me on all machines we own except our new AIQ (and I'm teaching him the calculus about gems, placement, and levelling up Avengers).
Then fast forward to last Friday, a pretty depressing day for the pinball community, and I go pick up my son from school... where I find out he may be already eclipsing me as an engineer. He drew in CAD and 3D printed a freggin model of Time Fantasy!
Moral of the story - kids can still get into pinball.