I like the idea of the classes because it makes the game more repayable and gives everyone more of a set role, increasing cooperation. I think the current class system is perfect, its kind of a compromise for people who like and the ones who don't like classes.
The current system is far closer to TES series excluding Skyrim. so wouldn't a loose class system like Zenimax has planned not feel more like TES?
No because even when classes were in they did not preclude you from doing everything the game offered on one character. Your class merely stated what you thought of yourself as, and gave you suggestions as to what to focus on. I could choose Battlemage and go full thief/rogue. It would take a bit more time, sure, but it could still be done. With this system, not so much.
By the time my Oblivion character reached level 100 he basically was a master in everything. Also, there has been the ability to make a custom class as well. One of Skyrim's best changes for me was the elimination of classes. I've also played several classless MMOs before and they are always a lot more fun progression-wise. Everyone becomes VERY unique and the differences are more nuanced than "I'm a tank only, I'm a healer only and I'm DPS only." That gets boring to me, far too predictable and not dynamic enough.
ESO certainly pushes the boundaries as that, but no it's not nearly as flexible as TES SP games.