The title of the thread is talent level. My premis is that while recruiting is important, retention and development is equally important. In the 4 classes that ended in 2018, Nebraska lost a boatload of players. Players that would have been juniors and soph next year that aren't going to be around.
The reason it is important to show what the class was like (with guys like Lindsay, Gebbia, POB) and now, without those guys, is because in the OP you are counting them as part of the "talent level". They aren't here, they aren't part of the talent level here. That is like saying I made $200k over the last two years, but I lost $100k. What you should have, isn't what you have. You don't get to claim the lost $100k as cash on hand.
It is similar to looking back to 2014 and 2015, and saying the team should have been better because there were 17 4 star players that should have been juniors and seniors, but they were almost all gone, either transferred, never made it, or just weren't good. If those players had been around, it might well have been a different story, Pelini may not have been fired, he may have won an 11th or 12th game or a Big Ten title. But that wasn't the case. People still wanted to use those recruiting rankings as a reason Nebraska should have been better, Well, many of those dudes were like the lost $100k......gone, they weren't going to win Nebraska any games, sitting on their couch in Tempe, playing for TCU or the Royals minor league team, or following their girlfriend to Gainesville.