BOSE-X: You don't get a 61.75 CPL/IR. The small print states not for commercial privileges and you may only use foreign IR privileges on it if you take the IFP written or do the full FAA IR. All based on ratings must be valid on the underlying licence fir the 61.75 to be valid.
Currently and last handful of years, yes, you'd be right.
Some people who had their CPL validated to FAA CPL very long time ago (would have to dig out exact time/date) and somehow didn't lose the original foreign licence/privileges etc, may indeed have CPL rights of validation.
The advice given was, as long as I kept the basic foreign licence valid, medical etc., the FAA IR would remain, as long as the FAA rating recency requirements were complied with.
If the original state of issue does not do medical endorsements in the licence (there are few around the world), the foreign medical does not have to be current, so long the person has FAA medical current/valid.