I'm not sure Wiki can be believed. AFAIK the tanks the Sherman were mostly PzIV, who were often confused by allied troops for Tigers. The most produced German armoured vehicle was the StUG-III.
They actually did see that as a primary role for tanks. Thing is they faced the difficulty of the Atlantic ocean between their production base and the fornt. This meant they cannot accept failures as the Germans faced with their tanks in Kursk, were they send Panthers and Ferdinands into battle which still had teething problems.
Also AFAIK a tank with a 90mm gun needs a bigger turretring, meaning a bigger tank, meaning they take more space into the ships. In the end this meant that they could either ship 5 Shermans or 2 or 3 M-26s. Since indeed the Sherman was judged good enough in spring 1944 (and it really was at that moment) they decided to go with the (well-tested) Sherman, instead of with a not enough tested tank with 90mm gun.
I don't usually like to bring up videos, but this one by the Chieftain adresses the issues the US faced very well. I'd highly recommend viewing it:
He adresses the myth that tanks were not supposed to kill tanks at 9:50, from the American doctrine: "Attacking tanks frequently encounter hostile tanks unexpectedly. At other times they may be requered to attack hostile tanks in order to break up an attack or counterattack."
At 13:00 he explaines that tankdestroyers are used as a reserve when attacking and been put into action when large numbers of enemy tanks are encoutered. In the meantime, everything else that attacks is also supposed to kill tanks.
At about 15:00 he explains that US army didn't put anything into production unless they bloody well knew that it worked (unlike the Germans).
At about 16:50 he citates a document by the Army board (december 1944) that the T26E1 was not battle ready. Which is almost six months after D-Day. So the reason they didn't take Pershings with them at D-Day, was because they were not ready. What really you don't want is that instead of 5 Shermans, you got 3 Pershing of which a third break down before they get into action.
At 19:00 he discusses the timeline of the Pershing and concludes there is no way that a relable version of it can be build before january 1945.
Taking a new tank ito production needs time and testing. You can't reall rush them into service. Well, the Germans thought they could, and
they faced massive reliability problems.