In which direction?
Its certainly true that it is almost impossible to return to airlines after some years in bizjets, outside Europe (and increasingly, inside EU). Nearly all ask for an actual landing on x airline type, within one year. There are very occasional exceptions like Sunexpress Turkey, and obviously if you are on an ACJ or BBJ, its a different matter.
But moving back to bizjets from a stint in airlines, anywhere worldwide, is actually easier, in my experience. Still not easy finding jobs though, in any circumstance