In short, realistic with better terrain types of maps, they are more limited in size during a normal map.
if you get penetrated, it might hurt a system, turret drive, gun barrel track etc that you need to repair (We talking seconds), not tedious, but unrealistic, and lose one or more crew, which increase repair time.
Penetration values and angles, trajectories, ammunition types you can load, are the most realistic part of WT tanks. Some ammunition types have explosive content in them.
You also have a Tank sim mode in the game, but its more of waiting game in a good position for other side to make a mistake, or force him to do it by capture parts of map.
Another bad part is you might meet cold war tanks in a later WWII tank unless you go into scenario type missions, also you get bombed alot in realistic tank games, but you have good AAA capabilties, in the game bracket I play (early wwII early cold war)
They have newer stuff , contemporary tanks and planes but I like wwII tanks and planes (had enough of cold war during my service in the 80s, freezing my butt off in a tank the arctic part of Sweden