Why does the code limit only 42 overcurrent devices per panel?

I remember reading an article some years ago that addressed this. Seems at one time there was no limit and a very large fusebox at a hotel caught fire. This was in the days of rubber covered wire & this produced quite a bit of smoke which resulted in some deaths. In order to limit the available fuel, it was decided to limit the number of circuits.

You should also see 90.8(B)

Tom