PNG save leads to very high CPU usage in Photoshop

Saving a file in Photoshop leads to sudden big peaks in CPU usage. In that for about 10 seconds the CPU goes to full 100%, and other running programs (of which there are not many) are impacted by this.

This happens consistently when I test this with single layer PNG files. These file are 2048 x 2048 pixels, so not big at all. I have an up-to-date Windows 11, up to date graphics drivers, GPU enabled, plenty of memory, and an AMD Ryzen 9. But since a few weeks the CPU usage goes through the roof when I save even simple files like the PNGs I described before. That really should not be happening!

Does anyone know how to fix this?