Top 10 teams were skipping the NCAA Tournament into the late 60's to go to the NIT instead. I believe #8 Marquette was the last one to do it in 1970. New York had better media exposure and prior to the mid-60's, Segregation in the south was a problem for some teams.
It was just a different sport prior to the tournament expansion in 1976.
I agree with your last point: the tournament was quite different after the mid-to-late 1970s, but I think that the whole "NIT was better than the NCAAs" isn't quite accurate, at least by the time UCLA was running off wins. You didn't say that, I know, but some have. There were rarely even Top 10 schools opting out. Most were just not invited, as you'll see below.
By the first years of the 1960s, the NIT had a certain look: generally small schools, mostly catholic, often eastern or midwestern independents, with a school or two from further out. You'll notice in the list below many top 10 teams just avoided by the NIT all together! They are in italics.
Rarely, by the 1960s, was a team considered one of the best couple teams in the NIT rather than in the NCAAs. 1960, in fact, is the last year where more than one top 10 school went to the NCAA. And look at a year like 1965 or so, when a number of Top Programs were also the types of programs the NIT invited, and that, perhaps, in 1960 did not go to the NCAA (Bradley). Yet, in 1965, both St. Joe’s and PC went to the NCAAs over the NIT. Villanova wasn’t invited because they had two other northern independents rated higher than them,
not because they thought the NIT was better. Similar in 1964. Basically, by 1964, if you were invited to the NCAA and the NIT, you went to the NCAA.
One notable exception: in 1970, Marquette didn’t like its draw, so it went to the NIT rather than the NCAAs…which made the NCAA disallow that going forward.
To back up my claim:
1960 Final AP Top 20
Team, followed by post season
1 Cincinnati – Final Four
2 California – Runner Up
3 Ohio State – Runner Up
4 Bradley (IL) – NIT Champ
5 West Virginia – NCAA S16
6 Utah – NCAA S16
7 Indiana – (Not Invited Anywhere)
8 Utah State – NIT Final Four
9 St. Bonaventure (NY) – NIT Final Four
10 Miami (FL) – NCAAs
11Auburn – (Not Invited Anywhere)
12 NYU – Final Four
13 Georgia Tech – E8
14 Providence (RI) – NIT Runner Up
15 Saint Louis – NIT
16 Holy Cross (MA) – NIT
17 Villanova – NIT
18 Duke – NCAA E8
19 Wake Forest –
(Not Invited Anywhere)
20 St. John's (NY) – NIT
1961 Final AP Top 10
(Drops to Top 10 for a while…not me trying to fudge numbers)
1 Ohio State – Runner Up
2 Cincinnati – National Champ
3 St. Bonaventure (NY) – NCAA S16
4 Kansas State – NCAA E8
5 North Carolina – (Not Invited Anywhere)
6 Bradley (IL) – (Not Invited Anywhere)
7 USC – NCAA S16
8 Iowa – (Not Invited Anywhere)
9 West Virginia – (Not Invited Anywhere)
10 Duke – (Not Invited Anywhere)
1962 Final AP Top 10
1 Ohio State – Runner Up
2 Cincinnati – National Champ
3 Kentucky – NCAA E8
4 Mississippi State – (Not Invited Anywhere)
5 Bradley (IL) – NIT
6 Kansas State – (Not Invited Anywhere)
7 Utah – (Not Invited Anywhere)
8 Bowling Green (OH) – NCAAs
9 Colorado – NCAA E8
10 Duke – (Not Invited Anywhere)
1963 Final AP Top 10
1 Cincinnati – Runner Up
2 Duke – Final Four
3 Loyola Chicago – National Champ
4 Arizona State – NCAA E8
5 Wichita State - NIT
6 Mississippi State – NCAAs
7 Ohio State – (Not Invited Anywhere)
8 Illinois – NCAA E8
9 NYU – NCAAs
10 Colorado – NCAA E8
1964 Final AP Top 10
1 UCLA – National Champ
2 Michigan – Final Four
3 Duke – Runner Up
4 Kentucky – NCAA S16
5 Wichita State – NCAA E8
6 Oregon State – NCAAs
7 Villanova – NCAA S16
8 Loyola Chicago – NCAA S16
9 DePaul – NIT
10 Davidson – (Not Invited Anywhere)
1965 Final AP Top 10
1 Michigan – Runner Up
2 UCLA – National Champ
3 Saint Joseph's – NCAA S16
4 Providence – NCAA E8
5 Vanderbilt – NCAA E8
6 Davidson – (Not Invited Anywhere)
7 Minnesota – (Not Invited Anywhere)
8 Villanova - NIT
9 BYU – NCAA S16
10 Duke – (Not Invited Anywhere)
