Yes, if you get 100 points, your game will be sent to Overwatch
Hi, I got a game ban this morning from being overwatched, which shouldn't have been possible as I've been playing in a 5 man team of people I trust so I wouldn't get reported 11 times to trigger the OW. I had a game last night where I got over 100 points, and my friend said to be careful because over 100 points means you get insta Overwatched. Is this the case? I can't think of any other reason as to why I'd have been game banned otherwise, unless one of my good friends decided to troll me which I highly doubt.
100 points does not necessarily mean you automatically get sent to OW.
Anyone who says it is/is not really can't prove what they're saying because usually cheaters will have 100+ if they're rage cheating, but good players can also have 100+ especially if it's a game with bots on either side.
Either someone report botted you (no one can prove that report bots work / don't), one of your friends troll-reported you, or vacnet got you.