No, actually the axial tilt oscillates between about 22 degrees and 24.5 degrees over a period of about 41,000 years. Right now we are close to the middle. That chart depicts about 20,000 years, or half a cycle. Once it reaches 22 degrees, it will swing back up to 24.5.
It is not actually the tilt of the earth in space (as measured by distant stars) that is changing, but plane of the earth’s orbit. We measure axial tilt, “the obliquity of the ecliptic” with respect to the plane of the earth’s orbit.
Oh, well, that’s alright then. You had me worried, for a moment there.