There’s no gradualist mechanism that can cause glaciation, so, no, Milankovitch’s model is wrong.
Please elaborate on your post.
The cycle is of three components The Malkovich cycle, also known as Milakovich cycles, refers to the three variations in Earth's orbit that influence its climate over long periods. These cycles have different periods: about 100,000 years for orbital eccentricity, 41,000 years for axial tilt (obliquity), and 26,000 years for precession.
Dependent on how the three componets line up is what gives of ice ages and the weather we enjoy now.