There are a lot of variables that go into a decision like this... Family (both blood and "K-State family), personal reasons, proximity to loved ones with health issues, playing time, interactions with coach(es), etc.
All play a part and to varying degrees. It's not nearly as cut & dried as you all want to make it out to be. At the end of the day, there should be some level of happiness/passion that is inherent in playing the game and that was becoming a challenge for our guy.
The likelihood of him getting into the NFL is "iffy" at best. With that said, he's really got two more years of playing competitive football unless he opts for the arena league. Assuming that a "Boykin-esque" package was not created for him during the spring, then I understand why he might want to step down to a competitive FCS level team to play the vast majority of the offensive snaps and hopefully make a playoff run.
As a fan/supporter of K-State football, the selfish side of me is sad/angry/disappointed in this news. However, I also realize how short the window of "football opportunity" stays open. Lots of kids choose to go play at a level they can stay on the field full-time... It's just rare when it happens like this.
Personally, I wish the kid the absolute best in whatever he chooses to be and to me he'll be #FAMILY for #LIFE.