Quote Originally Posted by Andevom View Post
Summoner: Summons creatures to aid the party in battle. FFXIV's SMN does this.
Red Mage: Casts both black and white magic, battles with swords. FFXIV's RDM does this.
Dark Knight: Heavily armored, battles with Great Swords, uses Darkness-based attacks. FFXIV's DRK does this.
Dancer: Dances to both harm the enemy and buff the party. FFXIV'S DNC does this.

Main Series Chemist: Mixes items in the inventory to create various effects. I don't see that working in XIV as it requires consumables to work.
FFT's Chemist: Throws healing items = Useless in XIV. It's an initial job you use because you have no other viable means of healing people at that point in the game. Chemist abilities literally just unlock which items they can use. A starter Chemist, for whatever reason, has no idea how to drink or throw a Hi-Potion because I guess the glass vials they're in are more sophisticated somehow.
Previous summoners including FFXI summon big creatures and the job revolves around them. FFXIV summoner is a DoT mage with a pet.

Previous red mages are jacks-of-all-trades who have access to low-mid tier black and white magic and can also attack with sword. FFXIV red mage revolves around a dual cast mechanic and balancing CNJ and THM spells and can also cure and have a few physical attacks as a part of their rotation.

All dark knights up until now have been a DPS that revolves around HP reductions for greater power. FFXIV dark knight is a tank.

Dancers have traditionally been debuff only. FFXIV dancer has no debuffs and is a long-range buffer class.

The degree to how different they from the original are varies between the jobs, but they’re still different. It isn’t necessarily bad, but it still takes creativity and imagination to take some classic jobs and twist them in a way that works in FFXIV. I don’t know why that can’t be done with chemist.