Starfleet personnel never were particularly disciplined or educated in TOS. Leers and jeers were the norm; there was no indication of initiative from anybody who wasn't a bridge officer; and classic disciplinary measures were still in use, including a brig to which servicemen were readily hauled by unquestioning security personnel.
Echoing sentiments from other posts as well... a lot of the Starfleet personnel outside the bridge crew... and other Federation in particular (especially admirals) were downright batshit crazy and really difficult to get along with.
Or had hidden agendas, hiding horrible secrets, were secretly aliens, etc etc.
Even in TNG I noticed this device a little bit but it is certainly noticeable in most of TOS.
It really makes an unusual statement. Here we are in Star Trek, optimistic view of our own future in which Earth explores the galaxy and we have an armchair view of the "best" ship in this circumstance. It's just that most of the other starfleet ships or starbases they encounter are staffed by assholes.