The whole gimmick of MNK that has been unchanged since 2.0 is that it's a class that focuses on positionals.
Arguing that DRG gets penalized more than MNK for missing positionals is not worth it, both by pure numbers and the design of the classes.

DRG is more about managing oGCDs, namely when to use specific Mirage Dives, Geirskoguls and going into LOTD by lining it up with B4B.
For example; O1S you want to have a late activation of LOTD (atleast 2 B4B worth of Nastrond) and in O3S you want to have an early activation of LOTD. Your 5th Mirage Dive should be kept for B4B, because unless you're expecting some long downtime there's no reason to use MD right away.