UCLA played in a different age of college basketball, but if you want to rely on a UCLA run fifty years ago to attempt to make a point about college basketball today; it does not contradict the point that it helps to play a high level of competition in the months heading into the NCAAs.
The PAC 8 did not form until 1968-9. From the time that it formed, John Wooden won 6 national titles (1969, 1970, 1971, 1972, 1973, and 1975). UCLA went unbeaten in the conference just two of those years (1971 and 1972). In 1971, UCLA played 14 conference games, 7 conference games that were decide by less than 10, and 6 of those games were decided by 5 or less. In 1972 (UCLA's most dominant team), the closest game that UCLA played until the NCAA final, a five point win over FSU, was a 6 point win over Oregon State. Also, in the middle of each conference season when Wooden coached, UCLA would play Notre Dame who was a quality independent in those days. So, the best competition that UCLA would face all season in 1972 was in the conference or against a quality OOC game later in the season; UCLA was just much better than everyone else. That is not the same as Gonzaga going through the motions against Pepperdine, Pacific and Portland today.
As for Wichita State's 2014 season. In their last 17 games before the tournament they played two that were won by less than 10 and even those two were not super-close (by 7 over Indiana State and by 9 over Northern Iowa). In their last 8 heading into the tournament, the Shockers won by 16, 14, 24, 29, 20, 23, 22, 25, 14, Also, that Wichita State team had 3 future NBA players, and they were favored against a 24-10 Kentucky team; so, don't make it seem like Wichita State was hopelessly outmanned. In the 8 games leading into the 2014 tournament, Kentucky had played two OT games, a game decided by 1 (to #3 Florida), and three other games decided by 7 or less. So, yes, using Wichita State/KY as the example, the evidence exists that Kentucky may have benefitted from playing close/competitive games heading into the Wichita State matchup.
On a larger point, it's hardly controversial to think that teams/players benefit from playing against high quality competition; that is conventional wisdom, and helps explain why a Power 6 team has won the last 53 NCAA tourneys except for UCONN from the AAC in 2014. Maybe Gonzaga will mow through the tourney this year, but they aren't as battle tested as teams playing in the Power 6 conferences, and in a close game in March it may make a difference. Maybe it won't, but I'm not "spewing stuff without knowing much about (it)". I leave that to RJ.
We shall see.