I didn't vote since I didn't play OST, and I can't compare. But... It's too complicated for a casual player and likely not complicated enough for an advanced player is my thought on it.
Do you think any of the features regarding RO2 tanks puts casual players off?
Since there's no 3rd person view, it's hard on non-tank maps or non-CA maps for a new tanker to drive around without getting stuck. The stock maps with single tanks are small and cluttered. As well as the illogical or buggy reasons why you can't destroy or at least drive over some meshes.
I'd venture that RO2 tanks would be best enjoyed with an experienced human crew, but that is not likely to happen. If you're a noob tanker, and tanks always had humans in them, you could join a crew as mg and at least learn how to tank. Where to go on a map, how to protect yourself, etc. Just like now, where a new player can join as a rifleman and follow better players, SL's whatever and learn how to operate in the game.
AI in a tank are annoying. "Yeskomandeer!Yeskomandeer!Yes!Yeskomandeer!"
Then they get killed and you have to climb around to switch seats to drive/gun/drive. Not knowing what keys will switch you to what seat. Meanwhile, you're getting pummeled by either an experienced tanker or opposing ai, who can't miss. It's complicated enough that it's intimidating to someone who hasn't tanked before. They expect cartoon tanks where the tank is just an armored avatar with a big gun, not a small team operating a machine.
Don't forget that if you are the sole tank, and you come even close to sucking, actually, unless you fully dominate, people will ***** and moan the entire round about how you are losing the match for them. It's a role that like being a TL, takes experience and time to master or at least be decent. If there were more tank only maps that were played, where you are only one of many, you can suck and learn. Or, if there was a way to play alongside an experienced tanker.