(Try to ignore the closely bunched satellites; those haven't spread out yet.)
They're all in an inclined orbit, with the orbital planes regularly staggered about Earth's axis. So, the simple way to consider this is that the distance between these orbits is greater at the equator than it is near the poles.
An extreme to illustrate the point; if they were all polar orbits, all the orbits would intersect at the poles, providing coverage from all of the planes, whereas each location at the equator might be served by one or two orbital planes.
https://satellitemap.space/indexA.html
(Try to ignore the closely bunched satellites; those haven't spread out yet.)
They're all in an inclined orbit, with the orbital planes regularly staggered about Earth's axis. So, the simple way to consider this is that the distance between these orbits is greater at the equator than it is near the poles.
An extreme to illustrate the point; if they were all polar orbits, all the orbits would intersect at the poles, providing coverage from all of the planes, whereas each location at the equator might be served by one or two orbital planes.