I was gonna say something along the same lines.
That something feels a certain way to one person does not mean it will feel that way to everyone.
The idea that "jumping adds immersion" is very subjective to begin with. I think it adds mobility. However, that kind of mobility is only useful or necessary if the game design requires or at least utilizes it. FFXI never required jumping and did quite well without it. Other MMOs like Lineage 2 never required jumping and did quite fine without it. Myriad single player games have never had a jump button and did quite well without it.. Zelda: Ocarina of Time is considered one of the best games ever made... no jump button.
Dragon Age... very successful game. No jump button.
The Witcher... successful game. No jump button.
Most of the FF titles, very successful series... no jump button in almost all of them.
And so on and so on.
Jumping in a MMO that's not designed around nor requires its use is a preference, not a requirement.
And to take the other perspective on it... Adding unrestricted jumping to a MMO could actually hinder immersion. Why? Because seeing people jumping around like hyper bunny rabbits in a high leve and dangerous area is about as unrealistic as I think you can get. And yet you see it time and again... People running high level dungeons, with deadly aggro all over the place, yet they're jumping off staircases, jumping on tables, etc, jumping non-stop. If they're in town, they're jumping on mailboxes, jumping on fountains, jumping on buildings.. jumping off buildings... That is immersion-breaking to me.
That's why I prefer a jumping system that is restricted, entails some kind of stamina bar or something to prevent people from spamming it and, preferably, not jumping unless absolutely necessary.
