The thing is the HOTS report system is heavily flawed, it was a mix of automatic report system and human verified reports.
Blizzard workers would verify reports like Cheating and Griefing, something an automated system would struggle to check properly, the automatic system was taking care of Abusive language as it’s easy to check the logs of a player for slurs, and it was taking care of AFK, if a player is absent for 3 minutes (a bit too long for a 15-minute match, but that’s my personal opinion) or if he quits and gets reported it gets a Leaver status.
Now the game is on maintenance, all staff was moved to different projects as result the report system is working only in a “half” active mode, the griefers know that the reports don’t work as long as you don’t quit the game or use unfiltered insults, that’s why you can find plenty of posts about feeding Leoric with 20+ deaths etc.
My personal experience with old report system below, do not read its kind of rant, haha:
Even when the staff was present, some of the suspensions they passed were ridiculous, for example i got suspended 3 times back when HOTS 2.0 came out, the first time i got suspended i was simply sarcastic without being abusive, i was often using something like: “Hey, can you call your older brother to switch you? We need someone reliable” (in case if i had a feeder or a troll). They didn’t like that, i was suspended for like 3 days or so, i came to the forums to check for the reason of suspension and contacted the moderator, they just told me to not be “sarcastic” as it might offend people etc.
I was reluctant but complied, i though “gosh, how many snowflakes they have to get offended by that”, but fine i stopped, i was thinking that it doesnt help to win the game so i focused on trying to win, the second suspension was because i called a Falstadt who deliberately didn’t used his ult for the whole game, i checked the replay he hasn’t used Gust a single time, i called him a troll, i got suspended for calling a Troll - a Troll, the moderator answered that even if he is a griefer or a troll to not call them trolls as it still might offend them (facepalm) and just silently report them. (it was a 1 week or so suspension).
The third suspension i got was really for nothing, i was playing alone in ranked as a support main and i was queued with a group of 4 people, they didnt liked how i healed so they just began blaming me like (“f*g Anduin ruined use the game” etc.) when i was ALWAYS near them pouring all my mana into healing, i wasn’t the best healer but i still wasn’t afk or feeding, they simply mass report me, the Appeal i made on forums was declined by the moderator saying that “I woudnt get reported if you didnt do anything” any attempts to reason with them like “check my chat logs, they are all clean” resulted in nothing, they only answered that i need to play with “friends” to avoid such situations.