And an infantryman with an anti-tank rifle could take out the M-10, M-36, and M-18. As could a PzII with its 20mm. As could every light anti-aircraft gun in the Luftwaffe's inventory, and every major German tank could take them out from as far as they could see them.
One has to take into account that both armies eschewed tank vs tank combat where they could. That Tigers would shoot the hell out of Shermans should be expected, you are talking about tanks that where in two different classes medium tank vs heavy tank
the comparable vehicles to the Sherman where the Panzer MK 4 and the T-34. The Sherman's armor was not notably worse than a Panzer MK 4... its main issue was that its 75mm and 76mm cannon variants lacked the punch of the Pak 40 and KwK42 high velocity 75mm guns of their German counterparts
Guderian correctly points out that tanks are more useful weapons of war than assault guns.
The Sherman's main two faults for service in its class are
A: The gun, which could be remedied by rearranging the turret configuration for a 90mm piece or just borrowing the high velocity British 17 pounder anti tank cannon
B: Crew training, there is significant and numerous anecdotal evidence that Sherman crews where just tossed into the frying pain with very little familiarization or time to run exercises with their unit... there is a HUGE difference between a green tank crew in a Sherman with little or no combat experience in Normandy vs a Panther or Panzer MK 4 crew with years of service in Russia to their credit.
To make the armored forces perform better, besides training and improving the M-4, the war office would just need to not stone wall the Pershing tank which could serve the same mission profile as the Tiger and the IS-2
also it would have helped if the infantry themselves had anti tank guns capable of knocking out a tank (57mm was no longer sufficient in '44)... the Germans by that point had numerous high velocity 75mm's and 88mm towed pieces that freed up their armored forces for other adventures than protecting the infantry