No, Election Day is not a paid holiday, or even a recognized holiday. Public schools are generally out (at least the ones used as voting precints) but folks have work, and typically most "in person" votes are cast after 5pm (after folks traditionally leave work).

Mail in voting has been something that the elderly, infirmed, workers, and folks in the military have done for decades. It's remarkably secure and quite auditable. The issue the right has with it is that the folks that vote by mail (the military notwithstanding) are typically democrats.