It's been at the snap for at least 20 years and probably longer.
It's just that teams now use that entire time that they are setting the ball and the chains, and then using the entire 25 second playclock on top of that. In the past, they didn't use all of that time.
Maybe conferences have different rules. I remember a Purdue-Minnesota game just a few years back where after Minnestoa tied up the game with only seconds to go, Purdue got the kickoff and completed a long pass to past midfield, in-bounds, with only 1 second left on the clock. They rush the FG unit on and snap as soon as the ref signals ready for play, in order to get the play off before time expires, and kick the winning FG. The Minnesota bench was whining that Purdue couldn't have gotten the snap off in time.