I've grown sick of trying to place in competitive matches, only to have "team" mates throw the match.
from my experience those tend to be the exception. just 'avoid as team mate' and move on. you have 3 slots for this, just enough to get rid of the worst. yes, silver/gold is hell
but sometimes the team is so spectacularly bad that throwing (or just practicing with your favorite char) can become a sensible option. you might get tired of healing them, of trying to herd them together or tired of not getting any heal or left alone on the point. it's just what it is: random matchmaking across the entire customer base. what would you expect? just take it easy, having fun and positive attitude and you will get the most of it and next match will be better.
With this in mind, my opinion is "in flux" regarding whether Frontier should do more to stop griefing in ED.
since it will emerge anyway if players have a minimal degree of freedom (as you show in op), it's an assumed part of the design. some games offset it with mitigation measures (like peanuts rebuys and eternal modules in elite), some even embrace it and make it a central part of the game (like 'harden the f up' in eve). in the end it's up to you, take it or leave it. no game can please everyone (although some try really hard).
for me being ganked isn't a problem per-se, at all. it only becomes obnoxious the moment you are ganked with some equipment that is locked behind several hundred hours worth of scraping wikies and performing game 'activities' i shouldn't be forced to. sadly, that's a pretty mainstream concept in games. so i just suck it up.
other than that, i don't see that being an issue in elite at all. there are several ways to avoid it, plus there's really nothing at stake. someone being ganked is as inconsequential as every other npc dying to farmers.