Anecdotally, having lived in Germany for a couple of years recently, there is a perceptible national character. The best way to understand it is to ponder the difference between a drag race and a rally race - in one, success means going as fast as possible; in the other success means getting to navigation points within a window of error. Or, with beer: in America success is discovering a new beer with a different flavor profile. In Germany, success is figuring out a way to even more precisely and consistently conforming to a centuries-old brewing standard. This, along with a kind of blunt speech that presupposes the listener to have little in the way of vanity or ego (or challenges them to not express it), is the "German character" as far as I can tell.

I suspect in part this was because they were burned very, very badly by the outward striving into the unknown that Hitler represented, and still having creativity and effort to apply turned inward to asymptotically approach perfect execution of the known.

Eh, I think that's a bit overblown. In theory, Germans are famously methodical and precise, in practice the rail network is falling apart, a major bridge in my city recently collapsed due to lack of proper maintenance, and "made in Germany" is mainly an encouragement to buy local, rather than buying for quality.

My experience of Germans, having lived among them for almost a decade, and having married one of them, is that you can usually find a counterexample to any supposed German characteristic just by looking around the room. If there is any overarching theme to the German psyche, it might be a tendency to conservatism (in the sense of preferring to do things as they've always been done), but at the same time you've also got radical groups on the left and the right that are a fundamental part of the democratic fabric of Germany.

I think there are some cultural touchstones that are very German, and those have an influence on how Germans think and act, but I think this can be very contradictory and it's difficult to draw a single picture here. For example, people are very conscious of antisemitism here because of how much it's talked about in schools and the media, and that informs national foreign policy. But at the same time, Germans, like most Western Europeans, have grown up in a time of peace and see war and aggression as a cardinal sin. Both of these inform the German response to something like the situation in Gaza, but the result averages out to a policy that's broadly in line with many other liberal European states.

All in all, I think you'll get more insight from phrenology than from trying to figure out the German character in too much depth.