I have had mine since release, so a bit more than 3 years, and yes my headband mesh has gotten noticeably softer. I dont do anything strange to it but do travel a lot with them. Shrugs. Doesn't matter to me, I didn't notice any discomfort and had to physically check the first time I heard about the issue. To me its real, but without consequence so it wont stop me from upgrading. Congrats on yours doing better.
My headband (white - should have gotten a different color) got yellowed pretty quickly despite having a silicon guard that sits between your head and the band, so only the top is exposed. The earcups get relatively dirty too. I would clean them frequently and that improves the look, but they never look like new, and they age fast. My headband is a little looser too. Its not an uncommon issue (just look at all the articles/videos with suggestions on the web). That said, they still function perfectly, are comfortable, and its just cosmetic.
I think next time I'll go for the darker color to hide grime and normal wear better. The non-cloth components look as good as day one for me. I just have a hard time replacing parts on a $500 set of headphones unless it results in listening quality improvements, and a yellowed headband or some slightly-stained earcups won't cause me to spend more.