The game will allow you to hire mercenaries.
For many people who play cRPGs, myself included, precisely for roleplaying reasons, using mercenary companions is flat-out not an acceptable option. We want a custom PC, but non-custom companions.
How well does that idea work with "I killed Wynne, WTF! I have no healers anymore, BioWare you're shit at designing games!" that hiring/creating mercenaries help fix?
Moving from Act 1 isn't the time you might lose a companion, the other cases will all be role-playing reasons/choices.
Firstly, the comparison doesn't hold because in DA losing Wynne or any other individual companion does not close off any important skill areas for you because there are other companions available with the ability to cover you and also because in DA the "classes" are essentially superficial and you can add any skill (ex. healing) to any of your characters.
Dragon Age classes are superficial? O_o You either never played the game or have terrible memory. DA classes are way more constraining than D&D 5e is. Only Warriors can tank/taunt, only Mages have healing/debuff/aoe CC abilities, only Rogues can pick locks and disarm traps. The stats requirements on weapon/armor also limit what you can use on a class because talent lines requirements pigeon hole you into specific ones. Mage are very much stuck with staff (unless you go Arcane Warrior and that is basically limited to the PC). DAO has only two mages, Wynne who default into healing/spirit healer and Morrigan who default into entropy and shapeshifting. The game has no respeccing unless you mod it. You could rely on health poultrices only but a mage healer/support is way more efficient, and less costly.
In D&D 5, making a longsword using Wizard who can pick locks/disarm trap is just a question of taking the right race and background. Nearly half the classes in the PHB can cast healing spells. At worst, play a Bard, it's literally a Jack-of-all-Trade: can heal, can boost rolls check with Bardic Inspiration/Jack-of-All-Trade/Expertise and with the College of Valor, can fight.
