One real factor in the multiplicity of programs is the number of bureaucrats and administrators that run them. It’s not just the recipients of the aid that benefit from all this.
Just like the post office, any “streamlining” will be opposed by a large squadron of govt employees.
I have checked and they have different amount of benefits for every zip code. Someone (or dozens, maybe) has a full time job calculating benefits for every zip code?
Half the budget of these programs stays in the bureaucracy I bet. We could cut the bureaucracy and save many billions without even touching benefits I would wager.