Thanks for the interesting information.
I don't know if Google wouldn't support .ru, but .com does offer other advantages. First, there are no restrictions on .com as there are on .ru. And if .ru doesn't support IDNs soon, then the gap will shrink even more. Also, the cost could be an issue. And lastly, if the sunrise period for .ru goes as well
as .eu did then there probably won't be anything left for the average person.