Back-up cameras are really important for kids who can't be seen in a rearview mirror. Those can be retrofit into an older car, but after having a kid I can see why these became mandatory.
A well designed car and proper driving technique make a backup camera unnecessary.
Many old cars have excellent rewards visibility without needing any camera- no camera will compare to a first generation Porsche Boxster with the top down for example, where you can directly see behind you by looking back. Volvo wagons are great like that also.
I also, as a rule never back anywhere that I haven’t seen directly just a few seconds before. I always back into parking places so I can see them facing forwards and not back up when starting out, and if I do need to back up when starting out I walk behind the car and look around first and then immediately get in and back up.
Also, show me the stats on how many toddlers are pancaked by lack of backup cameras each year per capita. That will inform me about how truly "important" this problem supposedly is.
A lot of old cars you could see clearly out of the rear windscreen. Modern vehicles seem to have dropped that.
I have not yet flattened a kid with my car, but I suppose there's still time. Also backup cameras are very important for today's vehicles which are gigantic monsters compared with cars of the 90s. My car is quite low to the ground.