Yes, this is true and from what I understand the push is for new cutoff dates but I would not be surprised if ECNL goes with grad year for high school ages if it’s decided new cutoff off dates are better for the masses.
By the time kids get to high school the difference of a year or so isn’t as substantial as the younger age groups. If you’re playing at the ECNL level most of those kids can handle playing high school varsity soccer as freshman. I don’t think they would determine it to be an unfair advantage as that would imply others could not red shirt also.
If a kid in high school struggles playing against seniors as a junior/soph playing Juniors or seniors. They probably aren’t going to be recruited for college.