I’ve seen new players try stacking quads or even dozens of cheap tanks, from M1 to sheridans to t-34. I tried it myself back when I was new. In Wargame, for pure tank vs tank warfare, this does not work.
The most effective tanks at tank vs tank warfare are the most expensive ones. It’s that simple. A 180pt tank will defeat an arbitrary number of 10pt or 50pt tanks, and a very large number of 90pt tanks, as long as it has ammo and is microed properly (aka avoiding sideshots and not getting too close). The reasons for this are rooted in how AP damage is calculated, and I’ll talk about it in other posts, but a newbie looking to get into the game quick needs to only know this: The more expensive your tank, the better. We call the most expensive tanks superheavies: the T-72BU, Challenger 2, Leopard2a5, M1a2, and so on.
For those tanks the only threat on the battlefield are other superheavies and planes and helos, which is why you should be far more worried about the sky when purchasing one. It is unlikely that you will lose your superheavy to another tank, it is absolutely dominant there, but revealing one to the enemy is guaranteed to summon their antitank planes, because planes are one of the few things that can kill a superheavy.
If you want to win at tanks, ditch the 40pt spam and get a superheavy. And be prepared to micro it very very carefully – avoid close range fights and always have a forest you can duck into if an antitank plane is spotted.