The problem is, that this isn't about Steinmeier as a private person. This is about the head of the German state who isn't welcome in Ukraine, this is effectively treating Germany like an enemy.
To put it bluntly, there are a lot of wars and other horrible stuff ongoing in the world (what the Chinese are doing to the Uigurs could also be called a kind of genocide for example), and no one here cares or expects Germany to care about it. We also have no formal alliance or whatever in place to help Ukraine, we just help out of goodwill, nothing forces us to do it. It isn't smart to risk this goodwill, yet Ukraine is constantly doing this to Germany.
And the way they try to weasel out of this doesn't make it better (by claiming that there never was an official request for a visit from the office of the German president - well no, of not a surprise, this group trip in question was organised by Poland, not by Germany).
I'm all for supporting the Ukrainian people, but their government and diplomats lost a lot of my respect in recent days.