No the German rounds smoked them. They were lightwejght. But they had numbers and diesel engines.
Not when first encountered - the Panzer III and IV crews got a really ugly wakeup call in the opening days of Operation Barbarossa when NONE of their 50-75mm shells could reliably penetrate a T-34’s armor sloped frontal armor at anything but suicide range; the KV-1 was even more nightmarish as pretty much everything but *some* of the 88mm flakcannon rounds just bounced off without leaving a mark, sometimes even at suicide ranges.
One assault-gun armed KV-1 variant, called the KV-2, is particularly famous. The crew of one decided that enough was enough and stood their ground - alone against the German 6th Panzer Division. That lone tank and it’s unknown crew played Horatius at the bridge and fought off the *entire* 6th Panzer for an entire day - until they ran out of ammo for the 152mm main gun, until they ran out of machine gun ammo, until they ran out of fuel. At which point, the Germans were finally able to close to contact range of the tank, breach the armor with antitank charges and then finally throw grenades through the breached armor to kill the crew (who were still firing back with personal arms from within the tank).
This wasn’t Soviet propaganda. We literally do not know who those brave men in the tank were because the only records that survived the war were the reports from the *German* commander of the 6th Panzer Division explaining why he had been unable to advance as directed. Soviet propaganda never really figured it out until much later.