Once you have real players playing special teams and not the guys who are going to get cut over the weekend, it will only take a few long ones or a kicker needing to make a tackle before head coaches do the math.

Every 1 yard gained on the kickoff increases the likelihood of scoring on a possession by 1%. (courtesy of In the Trenches with Dave Lapham talking to analytics guy ...average over the last few seasons) Better to hand the ball at the 30 to your opponent than risk them being at the 50 or getting your placekicker that you need for a FG at the end of the game hurt.

In the preseason the average return is to the 28 yard line. Any rational coach would happily trade 2 yards for zero chance of a truly explosive return play. Kickoffs will become a snooze this season.

they line up the old way. But onside kicks are somewhat restricted, in addition to declaring it and losing any surprise factor the team kicking must behind and it must be the 4th quarter.

But that's just off the top of my head, I might not recall accurately.

They basically are removing it from the game except in the one circumstance where the fact that it's still barely theoretically possible might be the only thing keeping fans tuned in.