I'd be very interested in a detailed comparison between whatever IBM was using at the time, the capabilities of the Z3, and whether it could have been modified to do the types of work IBM did. IBM's primary notoriety about all this is that they helped the Nazis to locate members of groups to be exterminated, but I expect that was a small part of what they did for the Nazis. But no IBM execs faced the Nuremburg Tribunals.
Also, I think Zuse at least somewhat well known in the U.S. The most basic computer books I have seen all have something about him. The information is available and common in the U.S. in elementary computer books like they use to teach schoolkids what computers are. I've read a fair amount of stuff about him in elementary school computer texts that I got in thrift stores and like that. The basic information about who he was and what he did is commonly available. Details are less common, so when I saw the post I immediately checked it out, whereas I more commonly open up pages in new tabs and read them after I've done my shopping through the feed. But the reason I recognized the name of the man and the machine is because of elementary school books that I picked up in a thrift store in 99.