This system is based on anarchic principles and 'free market' design, which means that there is no problem with the situation from a network perspective (albeit that the unenforced terms and conditions of steemit.com prohibit ALL bots).
I see that there are three main problems with the situation:
Bid bots do indeed invalidate 'proof of brain' and replace it with 'proof of wallet', which basically denies and blocks the magic of the Steem concept that draws so many in and who leave rapidly once they realise what is going on.
The platform is sold as being decentralised, yet top witnesses constantly receive large amounts of funds and by selling votes using bid bots, we have a situation where power is centralised among witnesses and bid bot operators (mostly). This is quite a reflection of the way that corporatocracy and crony capitalism has taken over the offline world. A key difference is that people can opt out of the steem network (and find it tougher to do the same in the offline world - except live in whatever jungles remain until the crapitalists destroy them all in their quest to 'win').
When top witnesses get to choose hard forks and those witnesses are engaged in industrial scale vote selling, this is not much different to politicians in our world who operate rigged elections (Which is most of them BTW). The network will gradually descend into one that favours the bot operator's methods and makes it ever more difficult to gain exposure without them. This is obvious to anyone with enough experience in the 'real world' to know how these situations play out over and over again in life.
It would be ideal, from my perspective, if the witnesses and community in general recognised this and took the necessary steps to resolve it.. But so far there is a kind of stand-off with a lot of frustration building up and little being done outwardly. Eventually there will either be a split or a collapse IMO... Unless, responsible change happens ASAP.
One solution has been to say that bot voted posts get moved to the 'promoted' list and/or that users have a button they can press to simply block out all promoted posts. The problem is that people could nefariously pay to upvote someone's post to hide it. So there would have to be a maximum allowable paid upvote amount, below which posts can stay in the trending page.. Maybe $20USD or something like that.
I am all for creativity - but recreating the problems of the offline world in a space that was intended to be truly innovative is not really helping anyone.
You're 100% right brother
I just made a post that explains a new way to resolve the issue of bid bots without overpowering anyone and thus maintaining a balance:
Bid Bots: Steem's Achilles Heel? I present A New Way To Solve The Bid Bot Issues And Reinstate 'Proof Of Brain'.