In the case where an appropriately licensed pilot is required by the provider of the aircraft (we'll presume an insured rental) to fly the aircraft at least as frequently as every 30 days, or having exceeded 30 days, have a check flight with an instructor, if that pilot does not log that check flight as PIC, how would they ever get out of the endless loop of "not flying PIC"? If the instructor logs the PIC time instead of the renter pilot, and the pilot comes back the next week to rent, they still have not flown as PIC in the last 30 days, despite having flown the previous week, as the instructor logged the PIC for that flight!
If it turns out that the renter pilot is so poor that the instructor had to completely take over, return the aircraft themselves, will not sign the renter for the checkflight. perhaps the renter pilot does not get to log the PIC, but then it sounds like that pilot is headed for some more dual flying anyway.
I feel that it is the responsibility of our industry to inspire and "grow" new pilots, to sustain our pastime. We are certainly not doing that if a loop hole is used to deny them logging flying that they actually flew under their privileges! A flying club or insurance 30 day rule is not an element of the licensing privileges.
If they arranged for the use of the aircraft, were duly licensed for it, signed for it, flew it unassisted, and paid for it, they were PIC, and should log the time as such. Whether an instructor sitting beside them, or an air traffic controller on the radio, could have helped with that flight does not take away from the fact that they fulfilled the licensing requirement for flying the plane, so as to log the flight as PIC.