Maybe EPOS' non-gaming hardware fares better, I have no idea. But these headsets certainly aren't indicative of Sennheiser's own production.
The closest thing is probably the G4ME ZERO, which is based on HD 380, which in turn has another headset version in PC 350. Similarly, there's an open-back headset based on some HD 5xx model. These are okay and should have replaceable parts. They're not perfect though, and there have been well documented quality issues too.
However, Sennheiser also has a professional product line with models such as the current HD 26 or HD 300 Pro that have HMD counterparts. These should be rugged and serviceable, but potentially not the most convenient for regular users. I'm a huge fan of the older HD 25 and HD 250 though.
I have a collection of vintage headphones. It's been fun discovering how the products evolved. For my favorite models, I've snagged spares whenever possible.
According to my spreadsheet, I might have about 60 pairs total.
That being said, I listen to podcasts through speakers most of the time, so maybe it's time to move on.