Not a complete surprise
With the trivial performance gains vs. the outrageous cost to continue dropping node size in insignificant dimension, it's not a complete surprise that many customers may not be willing to sign up for 7Nm chips. While percentage wise it may sound like a big deal to drop to 7Nm in reality the potential gains are quite small and the yields likely rather low for the first or second design generation runs. Tweaking existing 12Nm designs may prove more fruitful for the bottom line.