We'll give you adverts but not the functionality you had before
I'm sure even Claude could vibe code the necessary changed to have the taskbar on the left without buggering about with the registry.
Further proof (were it needed) that M$ doesn't give a hoot about the average user and is happy to "depreciate" features that many users find invaluable.
I've had the taskbar on the left since W95 as a user of wide screen monitors and needing to have 2 pages side by side on the screen.
That said I'd like to thank @Nematode for posting that link