If lack of maturity predicates voting, then we're inconsistently disenfranchising individuals within classes. That doesn't seem very fair and I don't really buy

If lack of maturity predicates voting, then we're inconsistently disenfranchising individuals within classes. That doesn't seem very fair and I don't really buy feasibility as an excuse. "Sorry, but it's not practically feasible to give you the rights you deserve," is beyond the moral pale.