Allah judges us according to our capacity, circumstances and environment. If someone is born in a non-Shia family, is a decent person, really tries to worship and obey God, and didn’t have the opportunity to see the truth (12 Imams) then yes Allah may forgive or retest them on Judgment Day, and if they pass they can go to heaven. But if someone saw the truth and knew it was truth, yet he stubbornly rejected it, then such a person does not deserve to go to heaven (Allah may still choose to forgive if He wants to..but such a person deserves punishment). So we don’t say that all those who are non-Shia are going to Hell