Because, even in a world where you can buy assault rifles at the mall, it is generally only the upper middle class who are able to afford to arm themselves
The idea of “Everywhere I go it is high noon at the o-k corral and I need to be ready to quickdraw on a toddler at a moment’s notice” is a decidedly White American mentality
People are generally either getting rounded up at border control (where you can’t have a gun because other countries are sane), at work during a raid, or getting head bagged off the street. None of which are situations where pulling your EDC glock with one in the chamber is going to do much because they have body armor and assault rifles
Lame ass response, you can get a used AR for like $200. Brand new for as low as $350.