The problem with a lot of camera systems is that generally speaking, lenses don’t come in a one-size-fits-all design. This means that even amongst the same brand, different models could use different lens mounts. This in turn creates a problem for photographers who are looking to adopt a new system and would either have to deal with adapters or buy a new set of lens entirely, which can be pretty expensive.
However, for Canon photographers, if you’re looking to make the move to the company’s EOS R series of mirrorless cameras but you have a bunch of EF mount lenses lying around, you could be in luck. This is because according to a report from Canon Rumors, they have heard that Canon is developing a new model of the EOS R that could come with an EF/RF hybrid mount.