Who is this "they" that doesn't make 2.4 liter motors anymore? Honda is building the by the thousdands in the good old USA. So are Jeep, Chrysler, Hyundai, Kia, Mitsubishi, and Toyota. Ford and Mazda have 2.3s -6 cubic inches smaller. The GM Ecotech will be around for years; someone posted a Sumitt Racing ad for Ecotech crate motors recently.
What will change is the internal workings of these motors. Direct injection is standard on new cars & the rule writers will eventually have to deal with it. We have leak troubles at 40 psi fuel pressure so it will be a learning curve for sure.
I have left the midget owner ranks because I am tired of the rules BS. No one tried to "level the playing field" when the V8-60 finally was replaced with compact OHV motors in the early 1960s. No club insisted you run a Chevy II; they let the racers figure out what worked and what didn't work.
We put 5 years into getting our Hondas sorted out only to be banned/restricted because other racers' self esteen was hurt. Racing is not Bible Camp kiddos. You work on your stuff and if it isn't fast enough you work harder.