Is there any official statements what is and what isn’t reportable as “gameplay sabotage”?
To me it seems that this won’t ever be reportable unless you just keep jumping off the map or stand afk and just tap sometimes to not drop afk.
Everything else could always just be attributed to “player is just really clueless”, even things such as not healing as support are not reportable afaik because you are allowed to play any character any way you want.
Google Overwatch Code of Conduct and also look up the terms of service. Should answer any questions you have.
I checked it coz i wanted to knwo too! it says nothing
“Behaviour that intentionally detracts from others’ enjoyment (such as griefing, throwing, feeding, etc.) is unacceptable.”
So what is throwing and feeding? could be ANYTHING depending on who asks…
for one guy throwing is already picking the wrong counter, but we KNOW that is not bannable cause Blizz said so.
A support who is not focussing on healing but rather dpsing is not throwing. There are a lot of top support players who will say to do this as an Ana player for instance.
exactly I was even commended for my dps Ana play 
but so it just means what we already know: game play sabotage can be anything for one person and nothing for another except if u jump into illios well all match. and then u could just say u were practicing lucio and it might not even be sabotage just learning lol.
there’s literally nothing else that can really be reported for
It is intentionally vague.
The general rule is we the players decide was is and isn’t acceptable. If someone is reported enough, they are clearly doing something disruptive and they get actioned (because it take so many reports to actually get actioned).
The reports will be subject to review by a game master though.
You can have a lot of reports even though you are not doing anything that isn’t officially allowed. I saw Torbs or Bastions getting chain-reported just for playing the hero for example.
So it remains unclear what exactly (apart from the trivial stuff) will be deemed gameplay sabotage and what won’t.
True. But for GP Sabo, that is after you’ve hit the threshold of number of reports in a certain number of games.
But once you’ve hit that target, you are guilty in their eyes.