This is clearly false. The limitations on BasicMed are different from those of a standard medical certificate [0], and have to do with your physician's medical opinion about your ability to operate a plane. There are a few conditions that specifically require a new SI [1] but this is not some pseudo-legal/badfaith game.

[0] https://www.faa.gov/documentLibrary/media/Form/FAA_Form_8700... [1] https://www.aopa.org/advocacy/pilots/medical/basicmed/basicm...