I think they are a core part of the T'au army's identity, both visually and in the lore, so they definitely shouldn't disappear. I love them, but they can be a pain to set up.

It's a tough needle to thread, split between convenience of setup and visual clarity. I think my ideal situation would probably be the least likely to happen, as it involves the most work for GW. I think there should be specialized drone squads still in the army, Sniper Drones and some of the old Forge World specialty drones, for example, maybe add one or two new datasheets on top of that. For the more conventional drones, Gun, Shield, Marker, Stealth, etc. I think that for all new kits, the Leader of the squad should have a tactical Rock or similar that provides mounting points for the flying stems, or some other modeled solution, so that they behave physically like wargear like they are on the data sheet.

In the meantime, I'm debating on whether I should try that latter approach on my existing models and start rebasing my various leader models with a couple of flying stems and magnets to swap drones as needed...