So am I and so do I. I sympathise with your feelings but, personally, don’t agree with them. Of course, DEVONthink is not "cheap” software by any stretch of the imagination. But it is rock solid, reliable and hugely versatile software with some of the best support I’ve ever come across.
Each of us has to weigh the benefits against the cost but so far as I’m concerned—even though I may never use any of the AI features and even though I use DEVONthink only for personal matters—it is worth what I’ve paid for the upgrade to version 4.0. My databases have very significant value to me as do all the automations that enable smooth filing and manipluation of 60+ years of diary entries (which I’m sure regular readers are thoroughly sick of hearing about 
).
I don’t seek to criticise your views but merely to provide a balancing view.
Stephen