Is full-field erbium laser (Sciton) more effective than fractional C02 for boxcar and rolling acne scars?

I've noticed doctors on YouTube who use a combination of full-field erbium with C02 fractional get much better results than using fractional lasers alone. Why is this combination of lasers not the norm for treating acne scars if it seems to be so much more effective? I've been to several dermatologic surgeons and they all recommend subcision with C02 fractional or Profractional. They don't mention the full-field option. Looking for some insight. Thanks!