[Matt B]

Thanks for these helpful points. I've immediately ordered a socket as shown on the picture. Wasn't aware these exist but for sure it will make live MUCH easier.
As far as 1-4 is concerned my idea was that someone tried to poorly kill the function by cutting a wire or connection and thereby also hit the backup lights. I'm not keen on that kind of upshift dictatorship either. But reverse lamps are legally required.

As far as parking is concerned I don't know what the previous owner preferred. But it's likely that she spent substantial amounts of time resting in reverse gear. I never use reverse, always 1st (or even neutral as my cars are parked on even ground). But it's good to know that extended reverse gear engagement may damage the switch.