That's right. So you'd have to convince these former World and Olympic champions and medallists that taking part in a fluff competition where they can very probably badly lose (only one winner, remember?) is somehow better for their image and PR, and more efficient way to earn money for their budgets, than simply starring in a show skating a program or two for the same pay... Unless you pay them substantially more than they could make from a show, I don't see them rushing in. Currently competing athletes and less decorated pro show skaters, maybe. Real former greats, no.
Well, skaters of the '90s had this same choice and many did participate in pro competitions. Even though they might lose 'very badly'...
And I suppose sometimes they did, seems that in 1998 pro Worlds, ISU allowed 'amateurs' to take part, resulting to Yagudin and Kwan winning, respectively.
Most athletes like competing and challenging themselves. Figure skating is not like fighting sports, where athletes may attempt to protect their image and avoid matches where they risk losing. And depending how the field is set up, 'losing badly' is not a big risk. Say a competition of 8 skaters, you bring in three top names, and five less well known ones. So the big names have an excellent chance of getting a podium placement, unless they really flop their programs.
Anyways, I agree there would be challenges setting up a "pro competition". Biggest Korean and Japanese names are likely hard/impossible to attract. Letting contemporary active top skaters to compete might make a result foregone conclusion a'la 1998. It's not clear how many skaters retired from active competition want to return, even if the rules would be less physically demanding than in ISU events.
I wonder if 'mixed concept' could work, first you do the competition part, then intermission and resurfacing, followed by 'gala'.
ATP Champions Tour was successful in 1990s, because it provided an entertaining alternative for (then-really boring) proper ATP tour. A professional figure skating competition would need to develope a similar sort of niche.