How to draw a favicon so that it is clear?

Question

Adobe Illustrator

I tried all the generators in the world, all the same, the elementary two letters on the favicon turn out to be "soapy", unlike very complex figures (the same Google), which look clear on other sites.

Imgur is generally the height of arrogance.
I draw in Adobe Illustrator

Answer 1

Very simple (however, it takes more time than feeding one picture to a service that will reduce it ten times).
Draw with pixel grid alignment, do it for each specific favicon resolution.