It's a sliding scale, and if we're looking for a stat to measure it, I'd have to go with usage. Since his 2nd season, Luka has had an average usage rate of 36.7. He's led the league 3 of the last 4 years. He's been over 40% a couple of times in the playoffs. Compare that to Lebron (career usage of 31.5 in the regular season, 31.7 in the playoffs) or Steph (31.2 during GS' dynasty run in the regular season and just 30.6 in the playoffs) or Tatum (31.0 since 2020 in the regular season and just 29.4 in the playoffs), and it seems pretty clear that Luka is on an entirely different level. Harden was always the comp. From 2015-2020, his usage was 35.0 in the regular season and 33.8 in the playoffs, which obviously still falls solidly short of Luka.I'll defend heliocentric players in that I think that LeBron, Steph, and present day JT are also extremely heliocentric players, they're just also versatile. I always used to say about AI back in the day that I loved watching Iverson play... for the 76ers. I'd've hated him if he played for Boston or Houston. And Iverson at least tried defensively.
As for Luka, I'll say that as much as I dislike Irving for being a noxious weirdo he's a lot more versatile than Luka. And ultimately I agree with your larger point, winning with guys like Luka is tough because there's really no margin for error. You need to surround them with 3&D guys that can convert their windows of opportunity while covering for their star on D (which the Sixers didn't have to worry as much about as Iverson was a perfectly capable PG defender).
If he had enough minutes to qualify, Luka would have by far the highest career usage rate of all time (35.7 for his career, Jordan is 2nd at 33.26, Kobe was 3rd at 31.85). No surprise that Luka is 1st all-time in playoff usage rate. Again Jordan is 2nd, so maybe that style can work, but I don't see a comparison (even just offensively) between how he plays vs Lebron/Steph/Tatum.