Alright, let's make it a four-tier system of riders. Mas is above Haig but still below Bernal. Finishing Top 5 in GCs is not a sure-fire predictor of reaching the top step of the Podium. His best shot at GC was the Vuelta that Simon Yates won. I'm sure Mas will have many more Top 5s to come.
I think the gap between Bernal and the Slovenians is much larger than the gap between him and the rest of the riders. I think he’s a better rider, but look at his Giro win. He beat a 33 year old career domestique by less than 2 minutes . Granted, Caruso is a very talented guy who was toiling, but riders develop at different rates. Bernal is the likeliest winner out of a field minus the Slovenians, but I wouldn’t consider him a lock either.
You have the Slovenians at the top
Then you have Bernal and Carapaz. I don’t rate these guys as unlikely to be beaten, but more likely to win because of their style and nature. They would enter the race as the favorite, but I wouldn’t be surprised if they finished off the podium either. Thomas would be here if he wasn’t old and likely at the end of his GC days (at least at the TDF).
After that you have guys like Mas, Almeida, Vingegaard (who could be rated higher if he had more to go on than one fabulous Tour), Landa, Lopez, Pinot, Tao, etc... Guys I expect to fight over the podium against the Slovenians but I wouldn’t be surprised if they won against the 2nd group.
Below them are the 1 hit wonders or teases- Buchmann, Haig, even Vlasov. Looked great at times but don’t haven’t shown to consistently be at the highest level yet.
Nibali I purposefully left out because he’s a former Tier 1 rider who is probably too old to be in tier 3, but if he came out and won the Giro in 2022, I wouldn’t be shocked, but I feel it disrespectful to rate a champion of his caliber anywhere beneath his stature even though his best days are behind him. Valverde would be the same were he not like 43 years old.
I left Froome out because he’s clearly not on the same level since his accident and I don’t think he’ll ever contend for a Top 15 at a GT.
Then you have Dumoulin- a clear Tier 1 rider not out of his prime age wise when his head is in the right place, who might be below tier 3 at this stage of his career because he doesn’t want to ride for GC anymore.
To be honest, I might even rate Carapaz above Bernal. I think Bernal has more potential to win any race, but I wouldn’t say he was any more of a favorite than the other if they were both targeting the race as co-leaders. Bernal might be more likely to win, but I am more surprised if Carapaz finishes off the podium than I would be for Bernal.