It was muuuch cheaper that way.

Because adding in repair stuff requires the supplier to provide documentation, frequently training, a parts manifest, guaranteed 10-20 year availability of spares, and probably about 50 other requirements I don't know about.

All of which add up to a rather large contract cost increase.

Possibly this boondoggle will result in the military putting in more reasonable "right to repair" terms in the contract, rather than insisting on the gold-plated thing I mention above, but more likely it will simply result in more cost overruns.