So IYO the Pz Mk III/IV were better than the British MBT of the era?
The Churchill and Panzer Mk IV both eventually had 75mm main guns and radios, but there the similarity ended.
The Mk IV had twice the speed and twice the range of a Churchill.
More important, the Churchill like the US Sherman, was designed for infantry support, not tank-on-tank battles.
The idea that a tank's first responsibility was to defeat enemy tanks (how can you "support infantry" otherwise?), took a long time to sink into the brains of allied commanders.
Even a US commander as famous as George Patton believed his Shermans were great at their assigned tasks, even though obviously inferior to their German opponents.
British Churchill:
German Panzer Mk IV: