I am not a developer so I couldn’t tell whether they have incompetent managers and developers as you’ve suggested. I can only use their public company metrics (and their product experience) as a proxy for how good their team must be. They have received $2 billion in funding from dozens of teams that do evaluate their dev talent. They maintain a dominant market share in a commoditized market. They employ top tier UX talent (of which is more in my wheelhouse). Judging by those factors it’s hard to imagine how they’ve made it this far with rampant incompetence.
As far as value, fortunately I have not experienced the disconnect that you have. As a 5-year paying customer both personally and as the admin for my company, I can say that I have found it to be highly superior in performance, consistency in up time, convenience in usage, and easier to manage than Drive and Box. I evaluated Box for a short time and used Drive for our agency for a full year before switching (it was much slower and far more difficult to manage). I’d also include iCloud in there but I don’t use that professionally so it’s unfair to compare.
All that said I can understand how — given your experience with Dropbox and knowledge of coding — your technical gripes are tied their rebrand. A brand is supposed to make a promise of quality and the product should deliver. To that end, i can understand why you see it as a failure.