are blind spot mirrors REALLYYY not a replacement for looking over your shoulder?

i feel like if the whole point of looking over your shoulder is to check said blind spot which is being checked by the mirror then you shouldn’t have to look over. i know it’s not technically recommended but its also not technically recommended to have more than 30 minutes of screen time a day or eat more than 4 fries in a sitting but nobody does that either. i just hate looking away from my front view like that.