How many have to exist before it can be considered "progressivism"/"diversity" then? Also can you provide those examples that occurred post-Disney? As a huge marvel fan it should be easy for you do. As someone who isn't a huge marvel fan I can think of several off the top of my head that occurred pre-Disney.
Miles Morales (Spider-Man), original character: Peter Parker/Spider-Man, first appearance: 2011
Jane Foster (Thor), original character: Thor Odinson, first appearance: 2014
Riri Williams (Ironheart), original character: Tony Stark/Iron Man, first appearance: 2016
Laura Kinney (X-23), original character: Logan/Wolverine, first appearance: 2004
Sam Wilson (Captain America), original character: Steve Rogers/Captain America, first appearance: 2014
Carol Danvers (Captain Marvel), original character: Mar-Vell/Captain Marvel, first appearance: 2012
Monica Rambeau (Captain Marvel), original character: Mar-Vell/Captain Marvel, first appearance: 1982
America Chavez (Miss America), original character: Joey Chapman/Miss America, first appearance: 2011
Kamala Khan (Ms. Marvel), original character: Carol Danvers/Ms. Marvel, first appearance: 2013
Kate Bishop (Hawkeye), original character: Clint Barton/Hawkeye, first appearance: 2005
Gwen Stacy (Spider-Woman, aka Spider-Gwen), original character: Peter Parker/Spider-Man, first appearance: 2014