My worry if this is implemented is that bots will hide in the shadows rather than be up-front. Right now there is an open discord for most of the mainstream bots. There is discussion for their pricing model, where and when they work, broadly speaking how well they work etc.
If you make it against ToS, regardless of the eventual punishment, it will push bots to be more secretive. So you'll 1) restrict a free market currently available to all and 2) make it harder to see what bots are up to and who is botting.
I suppose the best analogy is making drugs or prostitution illegal. Yes, it happens less when it's illegal, but 1) it's hard to estimate how much it actually happens 2) you lose revenue because it's all done under the table 3) it's hard to actually police because it's being hidden from prying eyes.
To me, the best answer to bots is to make bots unprofitable. I think the community has done really well to that end in the past few months (e.g., pushing rewards to higher leagues, removing RP from ghost cards, limiting RP from low-BCX cards). Soul-bound reward cards will do that even more. I think the better use of proposals and mental energy would be to develop systems that reward players more than bots. Someone mentioned KYC; I think that's a good idea (even if most crypto people are ideologically opposed to it). I'll keep thinking of ideas along this line, because I want to see bot farms gone.