Not at all, this is the size of a supermassive black hole, 50 million times the mass of the sun, like the one at the center of every galaxy. Sagittarius A*, the super massive black hole at the center of the Milky Way, only has a mass of 4 million suns.

They have always been a mystery, because it's not entirely known how these supermassive black holes could have formed, since the known methods of star collapse have upper bounds on size too small to account for these large black holes. The article mentions two hypotheses, primordial black holes somehow formed in the first second after the big bang, and direct collapse of large gas clouds into a black hole.

It's also very exciting to have an explanation for one of the many many "red dots" that were first spotted by JWST and have been very mysterious. If all these were super massive black holes without galaxies that would be fascinating.