It is too late for that, accounts are being selled anyway on the internet, there are too many spoofers and Niantic knows it. A lot of people is selling and buying accounts, even on youtube there is people giving away them in exchange of likes, comments, etc...
If they had a better customer service a lot of spoofers had been banned right now, they don't even answer or look at report emails, I have sent many of them, giving enough proofs that no one was actually there taking that gym at that time, all I got was an auto reply saying that they will look the case but I won't get an answer, lol it makes my laugh...It is like "Thank you for contact us customer, but we don't care, goodbye".
There is a pretty good video on YT of a group of guys filming a gym in the middle of a street at night, no one can be around, there are no buildings and no parked cars, it is in the middle of nowhere, and the gym is taking all the way down and 2 spoofers put a mon on there, they sent the video to Niantic a month ago, never got a answer, seriously? Those guys where filming the street and the pokémon app working on their phone at that time, showing more than enough proof to ban them forever, and Niantic does not do anything? When I saw it I could not believe my eyes.
Anyway, game will stay like this until it drops down that much that no one will buy accounts anymore and hackers will lost interest.