Exchanges can create rules, but there's a limit to how far they can push it:

If Nasdaq makes too many rules that investors or companies dislike, they'll list respectively trade elsewhere.

Developments in the rest of the market make stock splitting less of an imperative than in the past. Eg Robinhood and many other retail brokerages allow you to own partial shares now.

If you follow the logic of these recent developments, individual shares might become a thing of the past, and we will just directly trade fractions of whole companies.

(On your computer, rational numbers are easy to implement: just represent them as a pair of arbitrary-length integers.

Operations will be a lot slower than on floats or ints, but the exchange doesn't need to do too many operations per second. And market makers and hedge funds etc can use whatever approximation scheme they want in their internal systems.)