^This, exactly.
The best example of the cost difference I can imagine is the difference in price on Arsenal AK pistols vs Arsenal AK SBR's - They have the exact same components, receiver, barrel, etc on both a SAM7 pistol and a SAM7 SBR. The only difference is the paperwork and the stock components installed on the receiver.
The pistols are for sale for around $900, the SBR's are $1700+ Almost twice the price to get enough margin in it for Arsenal to even bother. Worse, there's no room for a markup on that SBR for SOT FFL's, so they make the same $50 or whatever for the NFA paperwork on that $1700 SBR as they would on a $350 suppressor.
By that math, and other similar pistol vs SBR comparisons, I'd agree that a factory SBR 10/22 would have to be over $1000 to make any sense for Ruger, and NOBODY with a brain is buying a $1000 factory SBR and waiting 9+ months when you can buy a $275 Charger today and file a $200 stamp yourself and have it done in ~2-4 months. Even adding a generous $150-200 budget for the stock/mags/etc you want on your SBR'd 10/22, you have a gun in hand 6+ months sooner and for $300+ less
Unless there are massive changes to the NFA, factory SBR's just don't make much sense.