It would be silly to have sneak attack not apply to a certain weapon because of a crit.
Flavor wise, the small damage die restriction even make sense since small weapons are better for making well-placed sneaky attacks. If you crit with that attack it makes even more sense for sneak attack to apply.
The restriction is supposed to apply when choosing your weapon, everything else would be unnecessarily complex.
It would be silly to have sneak attack not apply to a certain weapon because of a crit.
Flavor wise, the small damage die restriction even make sense since small weapons are better for making well-placed sneaky attacks. If you crit with that attack it makes even more sense for sneak attack to apply.
The restriction is supposed to apply when choosing your weapon, everything else would be unnecessarily complex.