Nope, that's exactly what Maintenance Mode means.
Minimal content updates and bugfixes, performed with the minimized Staff still working on it - all while the vast bulk of resources are channeled into the 2020 content that'll play no role in the entire meantime.
Following your definition, Maintenance mode technically wouldn't even exist - if only for a single GALnet article, a single Server-side bugfix or a new Paintjob appearing for the Game once in a while.
Anyway, pointless discussion and white-knighting denial of facts straight from the source.
I'll leave it at that, since it's all OT to the original Thread purpose anyway.
Nope. Windows 7 is in maintenance mode. Soon it'll be abandoned. Windows 10 is being actively developed, although you sometimes don't see major new features for months.
The same applies to games. A ten years old MMO that still has the servers running but doesn't get new content apart from security fixes is in maintenance mode. A ten years old MMO that got the servers shut down is abandoned. A MMO that gets yearly expansions isn't in maintenance mode, it's being actively developed.