What, you can’t enter a building without a doorman?
What happens when the elevator operators go on strike?
You can only be held hostage by those you give power to.
Whats worse is going into a public restroom with an attendant there to hand you paper towels and collect tips.
Of course one can enter a building without a doorman. That’s part of why they’re there: to keep people you don’t want in the building from entering. The job is a genteel form of security guard that also does the courtesy of opening doors for the residents.