Why did SE decide to make the three new classes not require base classes?

[Felis]

Because in all honesty, base classes are redundant. We didn't even have jobs when the game first came out, but they wanted traditional FF jobs but didn't want to remove the new classes. So we got stuck with this awkwardly planned system.

It is because FF XI players complained that the classes were not like the FF XI jobs and that they want the classic FF jobs they knew from XI in XIV.

In old 1.0 classes worked more like weapon classes. You leveled a class to get better with the weapon and learn more weapon skills. Once learned you can use the skills with every other weapon (but weaker than with the origin weapon). Except the skills that were bought with Guild Marks in the guilds. The character had his own level with the physical level and stat points were earned with the physical level and not with the class rank.

When was the last time you used a Class?

10 minutes ago. The BTN.