Not headsets, but Bose ANC headphones have used a 2.5mm jacks for years (and still do). They give you a 2.5 to 3.5mm cable, though. I imagine this is likely jus

Not headsets, but Bose ANC headphones have used a 2.5mm jacks for years (and still do). They give you a 2.5 to 3.5mm cable, though. I imagine this is likely just to drive cable sales, though, as there isn’t any real reason you need the 2.5mm jack on their relatively big headphones.