To be clear, I do think forfeiture is a viable option, one of many to consider. If the TP level is reached, then the community has effectively deemed the bot's action to be damaging. Any acts of the bot which produced gain (Steem, SP, and SD/SBD) would be forfeit to the community, rewarding those who identified the caustic bot. Seizure occurs in the real world all the time. If a thief steals money from your pocket and is caught, they don't get to keep the ill-gotten-goods.

This is one of many penalty options the Dev's can choose. Personally, I think it would be a powerful one. Financial disincentives can be highly effective against financially motivated anti-social behaviors.