As long as they qualify via their respective national championships and/or qualify via their national federation's selection committee - and they are obviously in good, competitive shape, I think it's OK.
Brian Boitano wasn't given a 'bye' to the 1994 Olympics. He had to earn his spot at the 1994 Nationals, where he was defeated by Scott Davis. Boitano competed at Lillehammer as the US silver medalist.
Katarina Witt also had to qualify for her spot on the German figure skating team so that she, to, could compete in Lillehammer. She competed at the Europeans and had a disastrous short program (Robin Hood) where she missed all of her jumps, but she rebounded in the long program and just barely qualified for the team.
I would be really surprised, however, to see any retired Americans return to the eligible ranks to compete at the Olympic Games. There is too much talent in the men's and women's fields for a "retired" skaters to qualify. But I suppose it's possible, just not very likely.