Kaffe Fassett has a Wikipedia page. I gather from it that his impact specifically on quilting has been 21st century, although his work in textile design goes back much farther. I first heard of him when he appeared on Simply Quilts. I was surprised to see he's 82 years old. He is so young in spirit! As for Tula Pink, she clearly is not old enough to have had influence on quilters more than 40 years ago, so she definitely qualifies for this list. I particularly love that in addition to fabric designs she has created some machine embroidery quilting designs which I found on the Embroidery Library website.
The use of the embroidery machine to do home quilting is yet another recent innovation, although technically, the general principle of it is probably what has created such items as the cross-hatched double sided machine quilted fabric that has been available in fabric stores and in ready-made clothing and bedding for decades. Computers have enabled much more complex designs and have made them available to home users over the Internet.