All discussion about favicons recommend creating favicons of different sizes to target different clients. See this answer for example: Does a favicon have to be 32x32 or 16x16?
My question: Is it really necessary to generate favicons with so many different size? What if I created one large favicon of size 200x200? I see various browsers like Chrome and Firefox automatically scaling it down to display a pretty scaled-down favicon in the browser tab.
What's the problem in going for one large favicon of size 200x200 then?
Note: I want the favicon to work on any device browser that conforms to the standard (if there is one for favicon). For example, if iOS Safari violates the standard then I am not too bothered with supporting it.