I doubt that 10xGPT3.5 > GPT4. There are a lot of tasks that GPT4 can do and GPT3.5 just cannot. Also, in such cases I find that GPT3.5's hallucinations are quite consistent, so such a method is probably not gonna help.
Imo stuff like this can have applications in a narrower set of problems, where you can also further finetune or simple prompt engineer a model to have a much higher accuracy. I do not think that they can become the bases in which database work is gonna take place in general, but it could be used to automate certain types of tasks that would be too hard/complicated to automate in a classical programmatic way, but not too hard/complicated a real intelligence to be needed to solve.
Good and bad itself depends on the perspective. Good for Hasbro? Can be argued I guess, depends also on its current economic situation and a lot of things other people may indeed not have the best knowledge about. Good for the players and fans of DnD? Good for those who actually work in the company and got laid off, or the remaining staff there? Almost surely not. This decision is not taken on their behalf and does not serve them in any way. And considering the popularity of DnD there is no surprise that the issue is going to be approached from an employee or player perspective rather than an investor or manager one.