In the wiki link states "Until the 19th century, most mathematicians considered the number 1 a prime, with the definition being just that a prime is divisible only by 1 and itself (Note it is not I redefining the definition of primes) but not requiring a specific number of distinct divisors...The change in label occurred so that the fundamental theorem of arithmetic, as stated, is valid, i.e., “each number has a unique factorization into primes". The wiki page on the fundamental theorem of arithmetic states that it is a hypothesis.(snip wiki; In common usage in the 21st century, a hypothesis refers to a provisional idea whose merit requires evaluation. )

As I said a redefinition of a definition may be useful i.e. in validaing a hypothesis but that does not make the redefinition preferred.

Preferred means preferred by a priori mathematical logic not preferred by a majority of mathematicians for convinence.(snip wiki; hypothesis old: clever idea or a convenient mathematical approach ).

The only mathematicaly logical reason for redefining a preferred definition is to show a that a nonhypothetical quandry is raised by the preferred definition.

PS Do not conclude that by making references to wiki that I am only now learning of the issues involved (a common slander posted here). I know the issues involved. That's why I know I can find them. I use wiki references to refer you to the issues involved.