The problem is lenses. Canon would have to come out with another complete line of high end lenses... And that takes time to design and facilities to manufacture... And at the same time as it is trying to update most of it's L-glass and already running into production volume problems.
Wouldn't the company Canon would acquire have it's own line of lenses and manufacturing facilities?
I wonder whether Canon could convert the cameras & lenses to EOS, e.g. mount diameters might be an issue.