I just explained why: They ruin interactions between players!
On a server with 10 people, when 2 people spend 30 minutes finding each other for a consensual fight, but then both mutually decide to dock and log off due to NPC's, the game design is problematic.
Afk traders in space never did anything to interfere with interactions between players. I'm not talking about things from an AFK trader perspective, besides as a trader you can have a fully neutral/almost fully neutral repsheet and not care about the NPC's at all. If the argument is that NPC's are beefed up to combat AFK-trading, then the design is deeply flawed.