I posted my setup on the Raspberry Pi Stack Exchange here where I was told this was unsafe, but I did not really understand why or how to fix it. The guy was telling me something about a polyfuse on the Pi Zero that might blow, but when I googled that, apparently a polyfuse is not a component on the Pi Zero, so I figured I would come here for a second opinion.
My thoughts are this, please correct me if Im wrong (in simple terms since I'm a noob). The power source is 5V 10A rated so if I were to just connect that 1 Pi shown in the photo it should be totally fine since it runs on 5V and it will only draw the amperage that it needs from the power source. Alternatively, I could also hook up 20 Pi Zeros to that terminal block in the photo, since cumulatively they would only draw 4-6Amps of the 10amps available (and they all run on 5V). This seems safe to me but maybe I'm missing something.