This is a case where the science evolved to justify a pre-decided narrative. This was absolutely necessary for an unsustainable food industry in an overly financialised nation(guess which). Don't waste your breath arguing logically. Just try your level best to ensure it doesn't occur in your local food economy, for the near future. Eventually, the GMO folks will reap.

If the potatoes last longer without going bad, then there's no reason to replace them prematurely. You have a predicted narrative that any preservation method you aren't comfortable is intrinsically bad because it lowers food quality, but I can guarantee you there are countless other forms of food preservation you have no problem with.

It comes down to superstition.