The relevance of many of these decks is overstated (Huntail/Gorebyss? Shedstall? Speed Arcanine?). Those decks may have won some tournaments, but they weren't "winning" decks. You could go to to a tournament and play seven rounds and not see a single one all day. And so, when we're talking about "the format" I don't think we're talking about decks that could conceivably see play--but decks that actually influence the overall environmental of the game. And, the truth is, those decks simply weren't that good. They had a modicum of success, but they weren't able to compete with a few of their dominating counterparts on a consistent basis.
The second point I'd made is that even when these decks existed in the same format, they weren't played at the same time. There were always two or three that were more dominant, and as such replaced the others as the most viable options. When Rock Lock was big, 75% of a top cut would be Rock Lock. Lumping all of these together is somewhat disingenuous, because it implies that all of them were equally viable within a two year period.
But, I do cede a little bit to your point about strategy. It does seem like perhaps there are less options there. I haven't really been active enough to comment on that yet.
Pheonixsong, I'll concede a bit with some of the decks I listed. Huntail/Gorebyss I threw in the list because it was something I tried running for awhile. Scythe is a deck my brother championed that sadly never saw much play either. But I'll stand behind a majority of the decks I mentioned. You pointed out LBS, Blaziken, and Medicham. The period of time I'm referring to is the '05-'06 and '06-'07 seasons, just before Gardevoir/Gallade stormed an entire format for a year. This was just after Rock Lock and Blaziken decks were so big. I didn't play during those years, but from what I've heard those decks were overplayed, as you suggested. My experience with this stems, as I said, from a two-year period.
To say that these decks weren't played at the same time was not my experience at all; it might have been yours, but here's what I played at Nationals in 2006, in round order: 1. LBS, 2. Medicham ex, 3. Muk/Weezing, 4. Metanite, 5. Ludicargo, 6. Dragtrode, 7. Flariados. I can't remember how many rounds there were, so I might be missing a few matchups (I vaguely remember facing LudiCargo twice, hmm...). Here's what I played at Worlds in 2006, in round order: 1. Bancham, 2. Dragtrode, 3. Ampharos/Quagsire, 4. Spinning Tail Tyranitar, 5. LBS, 6. Metanite. In the top cut I played against a Machamp deck that Gino was playing, then faced Queendom in the top 16. My brother lost to an Arcanine ex deck in the top 32. And finally, the Regionals decks I played against that year were: Metagross/Latios/Latias, LBS, Umbreon ex/Weezing, Spinning Tail T-Tar, Ludicargo, LBS. In the top cut I faced ZRE, LBS, Ludicargo, and Queendom. So, at some of the biggest tournaments I played in that year, I faced:
LBS
Ludicargo
Queendom
Flariados
Metanite
Dragtrode
Medicham ex
Bannette ex/Medicham ex
Muk/Weezing
Ampharos/Quagsire
Spinning Tail Tyranitar
Machamp
Umbreon ex/Weezing
Metagross/Latias/Latios
ZRE
So off that list I'll single out Umbreon ex/Weezing, Amparos/Quagsire, Muk/Weezing, and that Metagross deck as decks that didn't have much of an impact on the format. Oh, and Bancham, even though it was a "secret deck" for Worlds in 2006. The other decks though were played by tons of people. Queendom, Metanite, Ludicargo, Dragtrode, Spinning Tail T-Tar... these were the decks that made up the '05-'06 season, not to mention the Nationals secret deck (
Raieggs) or the winner of Worlds (
Mewtric). To suggest that this year was ruled by LBS is, from my point of view, misguided. Did you play much during this season?
Moving into the '06-'07 season, things seemed equally diverse. I remember Metanite and Raieggs being the best decks in the format at the time, but Raieggs lost a bit of popularity and Metanite had its counters (Destiny, Bandoom). I didn't go to Nationals or Worlds that year, so I can't comment on what I saw, but Absolution won both Nationals and Worlds, and my Regionals saw an enormously diverse field with Bannette/Houndoom, Shiftry ex, Metanite, Raieggs, Flygon ex, Delta Flygon decks, etc. These were decks that were top-cutting normally at tournaments, not random decks popping up here and there (like Arceus or Steelix today).
I guess the part that bothers me is the part you agreed with, the fact that in terms of strategy, the game is so limited today. I can either choose to play a deck that attempts to pump out as much damage in as little time as possible (Gyarados, Luxchomp), or I can slow everything down with trainer lock (Vilegar). Dialgachomp can do either, but only based on one's starting hand (the same can be said of Sablelock). I think of the decks people played back then, and strategies were all over the place. Raieggs could spread damage, Medicham ex could lock powers, Ludicargo could play a ton of single techs, Dragtrode manipulated energy, Polistall hid behind Fossils, Flariados was THE special condition deck, and on and on. Today, I can play speed, lock, or maybe a tank deck (Steelix) if people forgot to bring their Blazikens to the tournament that day. When I try to deviate from those two core strategies, my ideas don't hold up.
TL; DR: From where I stand, the '05-'06 and '06-'07 seasons were extremely diverse, strategy and deck-wise. I faced lots of different decks, and every set that came out seemed to give the players more options to use. Nowadays the game is boring because it revolves around the use of two core strategies: speed and trainer lock.