Do people go to Helll? Yes.. Our lady of Fatima I think said that souls are pouring into Hell. Do most, sadly it is the logical conclusion.

Here is a case where we know someone goes to hell:

"Whose sins you forgive are forgiven them, and whose sins you retain are retained." John - 20:23

In "Decet Romanum Pontificem" the pope clearly executes his ability to retain Luthers sin & formally excommunicates Martin Luther from the mystical body of the Church. Such an excommunication would have required Papal lifting either in person or with an appointed prelate, therefore we must draw a logical conclusion that poor Luther is not in the Body of Christ, and not a member of the Church Triumphant or Church Penitent. St. Pio said that he had a vision of Luther and he was in-fact in Hell, and that those that follow Luther's teachings are following Luther to hell, he never did clarify if the following was those born into schismatic sects or those that simply leave the true Church.

Important note: One might mistakenly hope that Luther is stuck in purgatory awaiting a papal lifting of her decision, but that cannot be the case, since he is excommunicated he is not allowed to be a member of the Church Penitent either.