I conducted some testing on your behalf!
I now possess a 2024 Model 3 including scroll wheel activation for Autopilot/TACC, without FSD, and equipped with the latest software. The Autopilot settings tab offers an activation choice for "Single Click" or "Double Click," analogous to Single Pull/Double Pull on the stalk.
In "Single Click" mode, only Autopilot is engaged, necessitating a modification in settings to activate Traffic-Aware Cruise.
In "Double Click" mode, the initial click engages Traffic-Aware Cruise, while the subsequent click enables Autopilot. The distinction is audible, since TACC produces a singular bong sound, but AP emits a dual-tone startup sound.