I agree with the spirit of what you are saying, but not the details. I absolutely research the company first. Aside from whatever improvement that may bring to the interview, I don't waste time on a company that I wouldn't want to work for. Likewise on any tech they use with which I am not familiar - I read up on it enough to know whether or not I'd want to work with it, and at least get enough sense of it to have a conversation about its overall design and purpose.

That research isn't for them... it is for me. I self-select out of jobs that I'd reject once I learned more about them.