The problem with this scenario is your rifles are next to the KT. What person puts rifles next to a KT? At KT max range of 50 the scatter is as bad as the IS2. At minimum 35 range against infantry unless they have AT weapons on them or they're attempting to snare. Any closer and you have potential threat of being shot at by a TD or getting snared.
you're is
Of course units are more likely to hit at 0 range. That's like saying the HE sherman should be tested at range 0 where it has the highest penetration of any nondoc medium, ontop of best utility and AI wiping power, all for 110F.
It's quite common in games because what the KT's good at is locking down a central VP. In such a situation with a one or two supporting units why should the OKW player worry about being snared if he is on the defensive punishing allied inf that tries to cap with his heavy tank that's relatively slow anyway?
I would dare say most KT engagements are around the 30-40 mark not max 50, yet in your test the KT was still doing decent damage at max range killing a model or two at 50. Yes you can make the argument "range 50 is not reliable or driving on move is not reliable" but the only tank I could say could were the unpatched comet and tiger ace. Both of those had obvious issues...
If the OKW player is overextending his KT without support of course a single firefly or jackson can solo it, but as others ITT have pointed out the KT still has a role with decent support. Buff the gun or armour and you're just repeating the same mistakes that have already been proven to ruin balance.