The chance of any team going unbeaten from and entire season is highly unlikely.
Granted, players come to college playing at much higher level than they did 40 years ago; a result of better facilities, better coaching, better competition and advances in physical preparation. However, the majority of the top players will not play more than one or two years in college and their best play will happen, not in college but in the NBA.
40 years ago, there were at most a dozen schools that dominated the scene every year and had a realistic chance to contend, and many would not play more than a couple of other top teams on a given year. Today, there are 30-40 teams that on a given day can beat any other team and with luck, they can make deep runs in March. The Big 12 alone has 4 teams ranked in the top 20 and every one of these teams will play the other teams in 6 games (3 home, 3 away), so the chances to go unbeaten in conference play or the season, even for a top team like KU, are very small; even smaller for other teams.
Of the 5 teams that started the season in the top 5, MSU. UK, Louisville, Duke and KU. all of them have already lost at least 1 game. Too much parity and zero chance of building a dominant team, with top players with more than a couple of years of experience.