I'm not saying it is a lie. It is just misleading to compare these values like You suggest. Such differences are just too small to have much impact on a vehicle vs at solutions performance. You are just overly focused on 20-70 front armour difference while forgetting that it won't matter that much on the battlefield 
A separate thing is the fact that many allied vehicles are more heavily armoured than you seem to acknowledge.
A rak is fine as it is imo. The at gun that is better than all other are, is probably the ZiS that has a crew of 6, shield, barrage and very good at capabilities. This one is really difficult to decrew (remember that cons have merge here too)
There is a huge difference in guaranteed to pen and 1 in 4shots will do no damage (statistically of course) on tanks that only take 4 shots to kill.
You see under rating the value of taking 0damage from a dedicated counter.
I'm well aware of the armour values of all, or at least most (there are a few that have been tweaked and I still recall the old values more clearly than the new ones) as well as the statical chances to pen. Rng can decide that a 25% chance to pen = 7 bounces in a row if it so pleases, however a 100% chance to pen will never bounce no matter how many shots you try. It's not negotiable. An armour value above the attacking units pen is better than one below it.amd again, allies have high armour units, but they are heavily restricted. The odds of fighting a KV1 are significantly lower than the odds of fighting an up armored p4.
While I do think the zis is under priced given its utility and durability, I have yet to see a zis retreat through enemy fire and arrive at base A-OK. probably on account of not having a target size nor speed bonus while doing it.
I like the 5th man in the rak as it helps bridge the gap, but I don't feel it needs retreat anymore on account of the 5th man.