You’re correct there are actually plenty of builds that don’t need much gear to handle P8, but they do need gear. But when you’re taking every bot and giving it an enigma, that would be taking away from the jah and ber runes you’d be trying to sell. In a market where timing is everything. The jah/bers they’re trying to sell along with the other gear they’d need to make the character P8 viable would have a ton more value being sold early. And by the time they even found enough of those runes to make up for that loss ladder would already be over because of how quickly the price drops.
Now sure there might be a bit of min/maxing they could do somewhere. Perhaps P3 with budget gear works, but they don’t do that because it isn’t worth the hassle.
Also I’m not sure where you got the perception that botters are botting in public games but that isn’t the case. Sure that one RMT site is running some baal bots, but that is just a PR move.
Again the efficiency isn’t there with botters running P8. Not only is the risk greater in a ban wave, but they’re directly eating up their product when their product has a limited lifetime of having value.
You’re not understanding the implications of running that type of a bot and what most botters goals are. One ber rune on day1 ladder can be sold for hundreds of dollars a ber rune right now is 1.50. If you’re using your jah/ber runes to make an enigma, then your shako, then probably some other varying gear that COULD have been sold sooner just to manage P8 then you’re losing value. What ever efficiency is entirely lost due to how the economy works in this game.