Bluetooth is not the solution for everyone. Many people still have wired, that also makes switching between different devices much easier, you have endless battery life, and why would you throw away functioning headsets?
Also speakers often connect with the 3.5mm input (with new Samsung TVs that is now also a disaster, friend of mine can no longer use his expensive speaker set). Also want to buy new ones?
Yes, I do get stuck a bit in the old, but I also don’t see why you don’t just leave that entrance in. Don’t you use it? Well, then you leave that thing for what it is anyway.
The choice is becoming less and less. The only reason they are disappearing is because manufacturers are very keen to sell their Bluetooth earphones to you.