It really isn’t.

It’s the Antwerp Port Authority in Antwerp, Belgium. Designed by Zaha Hadid. Pretty cool.>!!<

https://en.m.wikipedia.org/wiki/Port_Authority_Building_(Antwerp)

I saw several such hybrid old/new building combinations in Flemish cities. And they usually manage to pull it off.

Another example I liked is the STAM, the Ghent city museum. They also host a nice yearly jazz festival in the courtyard of that one.

https://stamgent.be/