Not exactly. There's different levels of 'realism' available in the different modes, from arcade which basically spoon-feeds you information and smooths out your vehicles' performance so that everyone is on a more even playing field, through Realistic which gives you relatively realistic vehicle characteristics and more direct control, as well as limiting you to fighting with your own country's vehicles and the vehicles of allied forces but still provides some hand-holds like third-person view and lit up targets, and then there's simulator, which is, well, like a simulator. It's like Realistic, but your view is limited to what the actual crew of the vehicle could see, whether that be cockpit view for pilots or turned-out, gun sight and driver port views for tanks, and only friendlies are marked out, with enemies only appearing on the minimap, and even then only for tanks. On top of that, pilots can't use the Instructor (which is basically plane-flying AI that keeps the plane operating about as well as it can manage, which in the case of avoiding things like stalls is almost magical), which also removes the mouse-aim feature, instead requiring you to either have a joystick or use the mouse-joystick, which is much harder.
The event cranks it up even further. There's no markers at all for enemy or friendly vehicles, so you have to spot enemies and identify them by eye. Due to this, it becomes possible to sneak right up on someone without them even noticing you, since it's very easy to get tunnel vision. It requires you to keep an eye out for yourself instead of relying on the minimap to show you where the enemy is, and it lets skilled players really pull out the advantages of their tanks without having to worry about getting massacred.