Clearly not, but it's hard to debate that the TNL ratio past ML45 (past 40, arguably?) is absolutely nonsensical.
Surely they could've aimed for a better ratio than the current, without making it too easy/fast.
My counterargument would be: why should they? The abilities unlocked by a level 59 sub are:
Aero III (BLM)
Carnage Elegy (BRD)
Regen III (SCH)
None of these are particularly useful, much less game changing. The primary reason to want ML50 is to consider a task complete, not to gain a new ability or be able to tackle specific content. Having the ratio set this high creates a long term goal for the theoretical people who actually enjoy playing the game. You are meant to play for years, if you do an hour or two of ML a couple nights a week while chatting with friends you'll still end up there eventually.
Foil and Fencer II being available at 58 is troublesome, and I think that it would've been a good balance change to reduce them to like 56 so that you didn't need such a large amount of ML to get a particularly strong ability like that on sub. But, aside from that, any feeling that you *need* a specific master level is self-imposed.