So no, adding a new race in FFXI would be COMPLETELY DIFFERENT than adding a new job.
Different from adding a new job in FFXI, but not different from adding one in any other game, as you explained.
A game like WoW requires new characters when either a new job or a new race are added, and people deal with it. FFXI/XIV happens to have the luxury of not requiring a new character in one of those cases. It's a bonus! Just because people are used to not having to create new characters as often as in other games doesn't mean they should have an absolute expectation that they never will.
If you have to use the words "people deal with it", doesn't that inherently imply it's a problem? People don't "deal with" things they like. Yes, FFXI players had the absolute expectation that they should never have to create another character. Yes, FFXIV characters should have that same expectation.
EDIT: Also, xp tnl nerfs and class nerfs don't have nearly a game shattering affect as a new race. Lowered xp tnl still benefits anyone who will continue to level new jobs (I leveled two to 75 prenerf and three after).
Just as new races benefit anyone who creates new characters.
New races don't benefit new characters so much as they penalize existing ones. They provide a minor benefit to new players (A new bit of customization) at the expense of SEVERELY PUNISHING your existing players (Either don't play the new class or start over from scratch)
One of the best parts of FFXI's job system (and FFXIV is already going to be the same in this respect) is that at NO POINT does the game ever FORCE you to start over entirely from scratch. No matter what crafts or jobs you level, you always have your character and your name, your reputation levels and your skills.
Even completely nerfing a job into the ground doesn't force you to make a NEW CHARACTER, it just forces you to choose between a new job on the SAME character or to continue playing your current one.
Adding a new race post release is the only way that a player would be FORCED to make a new character from scratch in order to enjoy part of the new expansion's content (the new race).
Again, if a new class meant a new character ANYWAY, then everyone has so many characters that "What's one more?" but I dare say the vast majority of FFXI players only had one character that they ever played to the point that it wasn't considered a mule. I had two mules, but only one main. comparatively in WoW, I wanted to play all 10 classes so I had 10 characters.
If BLU, COR, PUP, DNC, and SCH all came with the caveat that "You must create a new character to play these classes", the player base would have been in an absolute uproar. There is no positive benefit to be had from making your older players start a second character because their current one cannot enjoy a major selling point of the expansion (A new race).
Job nerfs don't preclude you from still playing that job (albeit needing to relearn it) or changing job but remaining on the same character.
And a new race doesn't stop you from continuing with your current character. Job nerfs are a much, much bigger deal than a new race because they actually negate what you've already achieved instead of just offering you more options.
Neither reduced xp nor job nerfs actually force you to start a NEW CHARACTER from scratch. Adding a new job does not force you to start a new character from scratch. Adding a new race -after release- does.
What's the huge, life-ending problem with starting a new character? People did it all the time in FFXI - on a whim, even - and they sure as **** do it in other games. You lose a few skills (I don't know exactly what will carry over between jobs in XIV) and you have to come up with a new name. Your knowledge of the game and the items/money you've collected can be transferred over, and those are the real time sinks.
Already covered this earlier in this same post, but to repeat: Job nerfs, at worst, result in the SAME character playing a new job. New races require a COMPLETELY NEW CHARACTER to play. So yes, they're worse. No, a new race doesn't stop you from playing your current character, but it does force you to split your time between two different ones.
As I stated before, one of the best parts of FFXI was that regardless of your job, you were always your character. Whether I was Mikhalia the BLM, Mikhalia the BRD, Mikhalia the DRG, I was still the Elvaan Mikhalia with the same linkshells, the same equipment, the same money... If I had to make a new character, that means I have to constantly send my money and items back and forth between characters (especially in situations like BLM/WHM/BRD where there's a ton of overlap).
If you want a game where you have to remember that all of your friends have 5 different alts and have to constantly log off and on to change class then go play... every other MMORPG out there.
In a game where one character can be every class, forcing a player to make a new character (and level those classes and skills over from scratch) is an unnecessary inconvenience with minimal to no positive benefit.