See here's the thing, stars do matter, to a degree, especially on individual basis but its the rankings outside of the top 10 that is not as discernible as people make them out to be. But with the five star first round drafted players, you have about 30+ per year according to the sites. So in a draft class you probably have what 50-70 5 star athletes available to draft from. 18% go in the first round so that's about 6 players which looks a lot like about 10% of available 5* players get drafted in the 1st round. You have about 200+ 4* athletes per year so around 400-500 are possibly available for the draft. With 40% that's about 13 players which means about 3.25% from that 400 player pool will make it to the first round. And of course the 3* and less is an even smaller percentage.
The point is however with the way these percentages are discussed it leaves a lot of people with the impression that over half of the 4* & 5* players become first round draft picks. And it's not the case. Maybe at best you are looking at 15% of all of those guys become first round players (we won't discuss or eliminate the ones who were busts or drafted improperly by the league). So yes stars matter, but with a much smaller percentage than people think. But lets poise this question, for the sake of winning on the college field would you have success with a team of 11 offensive and 11 defensive players drafted every year but none of them ever being drafted higher than the 3rd round? Because nobody, Bama included, have everybody drafted that are starters.