Boise State football coach Dirk Koetter announced on Thursday his departure from the school following a historic season for the Broncos.Koetter took to Facebook on Thursday evening to post an "open letter to Bronco Nation," writing "College football is rapidly changing and maybe not for the better. Conference realignment, roster limitations, transfer portal, NIL, lack of a governing body with any power are all issues that have to be dealt with."The Broncos season ended earlier this week with a 31-14 loss to Penn State in the Fiesta Bowl. RELATED: Broncos and BSU fans hold their heads high."BSU has two incredible leaders at the top right now in Jeramiah Dickey and Spencer Danielson," Koetter said in a press release. "These are two men of character and the right men for the job at hand.Koetter, in his letter, continued to discuss NIL and how Boise State is "behind in the NIL game."Our best players are getting offered between 2 and 10 times what we can offer. We are losing recruits in the portal to schools that are just flat outbidding us," Koetter said. "I know its not all about the money and Coach D and staff will undoubtedly continue to find the right kind of guys, but money is an issue."