So Why assume removal of Classes?

[Radacci]

snip

i'd guess lv cap would eventually stop at 100, cause of job skills every 5lv, would be weird to stop at 99.
and including class skills, that's going to be a lot. In XIV, there isn't even any special stats, like dragonslayer, for DRG. So the amount of skills you can put in for DRG, is somewhat limited anyway. So we don't *need* lv 1-100job, with only job skills.
For WHM, there's the possibility of like 10 more heal skills...that's necessary? not really. They can throw in a mix of atk/buff/heals, between CNJ and WHM. There's no job possibility lost, just cause of class.
Because of lv60 cap in expansion, it opens up the jobs, a bit more.
Also i'm guessing you're basing possibilities, on previous FF games that don't have anything to do with XIV.
We don't really know how many jobs there are going to be in expansion, and they can and do add jobs, outside of expansions.
DRK doesn't have any class, so we'll see what that leads to.

by taking out the class it will give them more tool for make each jobs different.

yes, and it would require lots more work. SCH/SMN share ACN; without ACN, they'd need to double the amount of skills, to differentiate them; not that i'm against it, but it's more efficient to have a class branch into multiple jobs.