2014 team had no McD's. 2011 had Kemba Walker. 2004 had Charlie Villanueva. 1999 had Khalid El-Amin and Rip Hamilton.
So it looks like 1 McD is sufficient, on average, if you have a Hall of Fame coach.
But things might be changing, with G league, Ollie's league, other opportunities for the top players outside NCAA. NIL might spread the top players around a bit more.
1999 had two: Khalid El-Amin and Richard Hamilton
2004 had two: Charlie Villanueva and Taliek Brown. This is in addition to numerous NBA players on that roster.
2011 had two: Kemba Walker and Alex Oriakhi
2014 is the only outlier with no McD's: Even that team had a consensus 5 star recruit in DeAndre Daniels.
This team benefitted playing with multiple NBA players and 5 star recruits throughout their tenure along with being coached by Calhoun.
It is necessary to get 5 star recruits every 2-3 years at worst if you expect to win titles. You can still have the majority of your roster full of 4 and 3 stars and still contend, but you absolutely need at worst one 5 star to win a title, and most of the time at least 2.
PS: The nonsense that Calhoun got lesser ranked players and was able to win without top talent just isn't true. Calhoun got plenty of top tier talent, which is why he was able to win championships in addition to him being a great overall coach. He was able to get 5 star recruits and McD's plenty of times.