No they will not. Because it is new, Canon will have IP protection on the communication protocols used in mount for many years to come. People can use the EF mount now because it is an old mount dating back to 1987 and any patents protecting it have long since expired.
It is possible that Canon might allow some third party lens manufacturers to produce lenses for the RF cameras in order to create an ecosystem quickly for the cameras, but IMO it is highly unlikely that they will do the reverse. That is the great thing about a new mount system - you get to decide who uses it, how and when. It belongs to you and no one else.
The only RF mounts you are likely to see are dumb mounts (the bayonet but no electronic signals) or something produced in backroom factories without consent in places with weak IP protection, such as China.