Except there has always been the case that there could be multiple users in a household, who all have different bike setups. MTB riders also have been asking for ages for a solution to spinning out because their bikes have too low of a highest gear for some situations, etc.

Zwift's Click has to run thru the Zwift app to get its signal to the trainer. Thought they had a technical reason for this, but I think maybe because the Play has to go through the app since it does things other than change gears.