I so rarely use the IS-2, even in team games, due to the 9 CP and high fuel cost. If it's wiping your squads then you're presenting it infantry to shoot--and thus, you're doing it wrong.
I wouldn't say that since infantry are often used to scout ahead of danger/ATGs/SU-85s before you decide to roll the tanks in which puts them at risk unless you got a Vet 2 Scout Car laying around. Add spotting scopes for risk of being called out for map hacks.
I really don't have a problem with the IS-2 one shotting since Ostheer has the tools in nearly all Tiers can pose a major threat to them, but it is annoying as it allows Soviets to have more control over portions of the map/VPs until you can make an effective push as you're at that point in the game where you don't want to risk your vetted infantry on capturing points.
Also Relic needs to hurry up and fix the Pak's Target Weakpoint. I could easily stun and finish off the IS-2 if they'd decide to fire the HEAT at the tank and not at the ground.