Minecon capes don't appear on Elytra

Special elytra textures don't seem to be appearing on any of the Minecon capes with the exception of the Minecon Live 2019 cape. I tested it with the 2011, 2012, 2013, 2015 and 2019 capes. I do not own the 2016 cape. 

Below are some pictures though not so sure how useful they will be.