I totally get what you're saying. I just think that it would surprise you how "bad" some players are. Of course this does not justify the people that literally admit to griefing by either not playing the game or by admitting it in chat, GM's should absolutely be more proactive in dealing with these players. Personally I am just not sure if giving less rewards to those players will solve it since the danger of false positives could happen depending on the implementation. Imagine a player who genuinely does not know recuperate is a button they had to put on their bar, then 0 healing is a stat that could trigger a false positive for someone who genuinely is just clueless. This is a bit of an extreme example but I have seen it happen. I've heard several stories of people queueing into pvp for the first time, not realising they were supposed to set up their bar in WDP.
Of course this now gets into another issue which is pvp tutorials and such... but maybe once that problem is solved they can implement a system that deals with lethargic gameplay like some people have suggested earlier in this thread.