Given the amount of flyers that folk get, I think your response rate is about 100 times lower than a few decades ago.
Not only that, web site development is either "web site in minutes" with some app or if they want something custom they tend to burn through developers at a high rate. Tough crowd. But keep trying.
What sort of results people are getting from flyers ( into letterboxes ) and what businesses are they still working well for ? I've tried fliers quite a bit in Sydney for web development, but I don't think they're working as well as they used to.