I think the point is that there are scenarios where large powers would disable/destroy each other's satellites without using nuclear weapons and we would be poorly prepared to replace them.

Is there any infrastructure of which this is not true? Every country, not just the Great Powers, has a large amount of installed plant which is the result of decades, in some cases centuries, of capital accumulation. And which modern weaponry can destroy in a matter of minutes. It's just easier to destroy than to build, and literally no industry has the capacity to rebuild as fast as a war breaks - if they did, most of those workers would be sitting idle in peacetime.

Compare the Battle of the Atlantic in WW2: Germany was trying to destroy merchant shipping faster than the Allies could build it, and failed; not because the subs were hunted down (though they were) but because the US refocused a humongous amount of industrial policy on building Liberty ships in a matter of days per hull. That was a massive national mobilisation, it would have been impossible to do so for more than a handful of capital plants, and it certainly wasn't going to be maintained in peacetime.

Edit to add: Though to argue a bit against my own point, satellites are perhaps uniquely vulnerable, even to nonstate actors. Lasers get better all the time and a satellite inherently needs to pass over other countries to do its job. Much easier targets than, say, electrical grids which can be defended by the internal-security garrison.

I think your parent commenter's point is that the satellites are used to detect launches. No satellites == no early warning == temptation to launch preemptively.

I think once satellites are in pieces while orbiting it’s not just a workforce problem to be solved.