I agree with what you are saying, too many fonts on one page is not in my opinion good typography. Good typography should be more about how you use fonts not about how many you use. By mixing say 2 or 3 fonts on a page if they are chosen well can make a good composition. Say you are doing a site for a restaurant and you have a nice script for the headings and then contrast that with a clean sans serif font for the body text and navbars you could still get creative with different weights, and sizes. Choosing fonts that play nice together is important too, contrast is good but not when they clash with each other.