This is wild! Duet Display, an app built by ex-Apple engineers has a curious toggle in the settings menu to turn off Airdrop, Handoff etc as well since it apparently screws up the remote desktop experience.

Apple also has introduced a beta feature called "Universal control" which allows you to use your keyboard and other peripherals across all devices nearby (ipads, other macs etc) I wonder how much of a performance tax these other features levy and if Apple tests the regression explicitly.