Deciding to changing from EF to RF would give a person the opportunity to switch to a different manufacture. Some of the expense could be minimized and offset by the additional cost the EF system costs you to upgrade.

The value of the comparison would have been before I bought the R5 and three RF L lenses.

The rule used to be that you bought in to the system with the best glass. That debate doesn't materialize on the forums as much as it used to.