Colourblindness knows many types, most can still see color. Some types even see more or shifted colors.

At least on paper it seems plausible to measure the colour detection cones per iris and then build a filter to strengthen color per eye for which detection is lacking.

The moment i realized they sold them without detailed personal eye scanning involved i knew they were a scam. Gimmick at best. Worst part is they seem catered to people as gifts for colorblind friends, thats just a way to obstruct people from analyzing them to much. What are they going to say? “I dont for a sec believe this overly saturated view is realistic and your gift sucks”? No, they will say “wauw thank you” and shove it in a drawer somewhere next day, never to mention them again.