Its like this in most MMORPGs. And I'm going to say this right now as PCMR. It is NOT the PS4's fault for this. Go play any other MMO (other than Everquest), and you will see the same silent treatment.

EQ is one of the few not like this due to the slower pace of combat. You pull a mob, one mob (more than that requires CC or wipe), and it takes about a minute or two to kill it. There's plenty of time between abilities and spell casts to be sociable.

One anomaly is Planetside 2. Being a MMOFPS you'd think the fastest pace of first person combat would lend to poor chatter, but due to the ingame squad/platoon voice, there's actually alot of sociability in that game. It gets even weirder that people are actually nice to each other.. in a FPS, that's F2P, and totally PVP. But I think it has to do with it being a MMOFPS, a rare genre (its one of two, the other being Defiance.. if its still up).

So its the speed and pace of combat that does this. Even ESO being action based is a bit slower paced and allows for a little bit (not much) of chatter. This isn't a bad thing. I socialize all the time using VOIP (in the form of Teamspeak) but that requires an outside setup with established friends.