Is there even any generally agreed upon glory years for DT?
It's not like Metallica, whose most tenured fans tend to think the glory years were everything until (and including) Justice. DT albums have been pretty varied over the years both stylistically and in terms of reception.
1992-2002
Go to just about any site with rankings and their top four most popular albums will be from that era (I&W, Awake, Scenes, 6DOIT). That is the consensus.
But that period contains Falling Into Infinity, which is generally considered their worst album. And Awake sounds nothing like I&W and had more mixed reactions. There are also plenty of people who were blown away by I&W and lost interest in the band after they released Awake. You have 3 very strong albums that nearly everyone would agree on (I&W, Scenes and 6DOIT), but that is over a 10 year period. Do 3 albums dispersed over a 10 year period make a glory years period? I tend to think not given the order in which they fell, alongside albums that are considered less strong. It's a far less obvious thing I think compared other bands. I used the Metallica example, where nearly everyone who's been a fan for a while loves those early albums. Maiden very obviously had their glory years from Number to Powerslave (maybe to Seventh Son but then again that includes a weaker album in there). As another example you could say In Flames had Jester until Colony. It's a more obvious case when the band sticks to one sound for a period and then suddenly changes it.
Consider this forum. The opinions here about DT albums are so wildly different. I am not sure you could pin down a consensus on any glory year period that doesn't contain albums a lot of people consider weak or just decent.
This forum is a tiny percentage of the actual fanbase.
Awake lost them some casual mainstream fans since there was no Pull Me Under, but the album has held up as one of their 3-4 most popular albums with the fanbase (again, go to most sites where you can rank albums and you will see this). And the band knows this, which is why it was heavily featured on the Along for the Ride tour in 2014. The only albums to date that have gotten the anniversary treatment over the course of a whole tour are I&W, Awake and Scenes.
Aren't those the only albums old enough to actually receive anniversary treatment (not including an unpopular album in FII)?
Not necessarily.
And while Falling into Infinity was considered a letdown by some at the time, it has aged well for many, so it calling it "unpopular" is hyperbole, and just looking at one site now (below), it is rated higher than four of their six most recent albums (and the two that are ahead of it, are barely ahead of it.
https://rateyourmusic.com/artist/dream_theaterAlso, feel free to notice what four studio albums there are rated the highest.
But hey, if you don't like that site, try this one:
http://www.progarchives.com/artist.asp?id=378Look at that, the same four studio albums are the highest rated.
(not counting the new one, which has two votes so far
).
Now, if someone wants to argue that the glory years of LIVE Dream Theater was 2000-2006, I won't argue that. They were mostly crushing it live in that time span, so I can get on board with that, but when it comes to their studio output, 1992-2002, regardless of what you or me or anyone else thinks of this album or that album, is pretty much the consensus for being their glory years.