Not true...since last April when we started hiring, I flew with several new-hire FO's (on the 744) that only had corporate jet experience (Netjets, privately-owned airplanes, and corporate-owned like a former Ford pilot on the G-IV or G-V).
But ALL have/had PIC experience...whereas, a lot of the FO's from 121 (majors, nationals, and regionals) don't necessarily have PIC time and experience.
Hope that helps...good luck.