The way Overwatch bans cheaters is by sensing if they have any background programs running that interfere with how the game works. These would include aimbots, wallhacks, invisibility, straight-up being unkillable, etc.
According to @carter_ow, a former professional Overwatch player, Blizzard has banned EVERY SINGLE PLAYER who has played Overwatch on Linux in the past week.
Overwatch is unable to run on Linux by itself, but players use an emulator called WINE (Wine Is Not an Emulator) to run Windows programs. This in and of itself is probably causing the system to detect a third-party ‘cheating’ program, despite there being no actual cheating.
Officially, Blizzard can rightfully ban people who play on Linux, as it’s not a supported operating system. Should they? No. No, they shouldn’t. First, it’s just rude. Second, it’s lost revenue. But again, this was most likely a mistake.
This unfortunate news coupled with the announcement that there will be no Blizzcon this year, and how they’ve lost a third of their player base in the last three years might be a blow to Blizzard’s shining public relations outlook right now. That was sarcasm, by the way.
I hope Blizzard realizes their mistake and makes it a point to fix their ban system and reinstate the accounts of the erroneously punished. It would score them some public relations points, while also just doing the right thing.