It has been. The default was to limit it to 1M in case there were weird edge cases with the larger sizes (16M is the largest it'll encode on disk without a for

It has been. The default was to limit it to 1M in case there were weird edge cases with the larger sizes (16M is the largest it'll encode on disk without a format change, IIRC), with larger sizes behind a tunable, but after a few years of people who knew this twiddling it, the default in 2.2 will be that the tunable is set to 16M.