ZGC (and the -XX:+UseZGC command-line flag) is marked experimental, which means that you always need to use -XX:+UnlockExperimentalVMOptions to unlock that option. However, some of ZGC's flags are incorrectly marked as product flags. This can be a bit confusing, since those flags (but not the -XX:+UseZGC flag) will show up when using -XX:PrintFlagsFinal, even though they are effectively experimental and has no use/meaning unless ZGC is enabled.

We should not mark any ZGC flags as product flags, until the -XX:+UseZGC flag is made a product flag.