I am not sure this has been proven (at least within the M1 or M2, I seem to remember RISC-V cores in other places but cannot find a reference right now, so I might be misremembering). I think the parent is overly enthusiastic.
What we know is that Apple is hiring people with RISC-V experience. And it would be very off-character if they did not have at least a team somewhere working on it. You can bet that they would jump on it the moment it makes sense for them.
Apple had Intel parts in various non-core devices long before Intel made it into macs.
Apple now has RISC-V cores as bookkeeping devices in the M1 & M2.
ARM can see the writing on the wall.