It actually is a strategic move. You can load a rocket with huge amounts of mass. It does not actually go onto orbit. The nuclear charge slaps the sand/dust into orbit. Colloidal gold is particularly effective. It will spread as individual grains. Gold is dense so a 100 micron ball can punch into 0.8 mm aluminum and the vapor explode. Easily makes a pinhole in 1 to 2 mm aluminum fuel canisters or satellite bodies. Gold plasma or vapor deposition will make a thin conductive film. That can short circuit electronics. If the initial plates are cubic meter scale then you can disperse a trillion particles in the 100 micron scale. If they are shot retrograde the colloids have two opportunities to impact per orbit and collision velocities are over 10 km/s.

If Russia, China, or USA does it the nuke is unnecessary and therefore not likely. For Iran or North Korea this makes a lot more sense. Wiping out the satellites takes out everyone’s satellites.

Even aiming at specific satellites will take out everyone’s satellites through a collision cascade (called Kessler syndrome). China tested an anti-satellite over a decade ago and the debris is still a significant fraction of the tracked debris in orbit. Satellites are often lost due to debris that is too small to track. If the debris hits a critical density we lose control of too many satellites and the collisions keep happening faster.

So you can one shot almost the entire low Earth orbit satellite network. After that satellites will be limited to skimming the upper atmosphere for a few months until the run out of fuel.