It would seem that we have some folks here who are, shall we say, new to aviation, and are not aware of past procedures on many older types.
While it is true that many new(er) types will not tolerate frost on the wings (polished or not), many older types (DC-3, as an example) can be flown quite safely with well-polished frost.
As for frost on the underside of wings on jet aircraft, B707's (again, as an example) had no restrictions whatsoever in this regard, so a few youngsters who, having never flown older types, will more than likely be unaware.