It doesn’t hurt anything. Just PvP feeds from trading and trading feeds from PvP. They are beneficial for each other. However, if you cut off trading, players that like PvP will be inclined to PvE and loot more often, and this can be weary at the long run. It is not entirely a bad thing if you think PvP is incorporated to the main game through challenges but still a dilemma.
True, but needed for a fast going 5 minute fun being irrelevant to the whole circulation of gameflow or isolated from it. If I like PvP and can not get my PvP build going in a short time, then two options here; I quit the game abit early to return to it or after a while I give up and try my best at PvE. Trading may look scary, but shortening the path helps the distinctive nature to apply.
Just because it can be automated you shouldn’t set aside small deals you can do with friends. You can not always play together for timeline differences with the other end of the world but you can come together, do some trading and go on your own way until next time.
Then what exactly are you playing a very low interaction genre for? Leaderboards are one of the staples as game revolves around PvE, maybe the most important ahead of PvP. Trading is just an alternate endgame where you can exchange and interact to get what you want.
People do that for a small challenge. What is even an ARPG without challenging anything beyond clicking at a screen and watching numbers grow? If I wanted something like that, I could always play Clicker Heroes instead of an ARPG or any other MMO.