I have cars never touched in my driveway that are speed density from the factory.. including my EcoBoost f150 they simply used air temp and map along with throttle mapping to reverse calculate the air mass. Works excellent and is the reason a properly tuned speed density setup works perfectly. Lately the oem have been moving away from mafmost aftermarket systems utilize speed density
on a street car, a maf is preferred
Look at OEM. There ain't no SD systems in OEM that I know of, all maf, at least since the 1990's (which are antiques)
ask yourself why
I'm pretty certain that if OEM's could save a $20 MAF and still provide the good NVH, fuel mileage, drivability, and reliability they would most definitely run the "simpler" SD system. $20 saved is a generality. If they built 300,000 cars all the same with SD (no maf), for a savings of $20 each, that's a savings of $6,000,000. I'm certain that if an automotive manufacturer was given the opportunity to save $6M, they'd do it. But $20 is a VERY general figure to throw out there, I would venture to guess it'd be much more substantial once you figure in the wiring, ecu, intake piping, airbox, and a bunch of other things that benefit the maf system and the sensor itself.
Actually this subject reminds me that I need to order some parts, doing a T4M0 94-95 GT computer in my 93 coupe 4 cylinder so I can run a slot MAF with it (turbo). The VAM system works ok but it's very limited and CRUDE.