People complained about how red didn't have a card for this completely imaginary cycle, then they printed a super good red card that fit the parameters, so I'm not really interested in equally imaginary reasons why it doesn't count. "This card is actually color {X}" is only actually interesting when it's a factual statement about metagame use (which is what the original Tarmogoyf comment was about), not when it's just a random way to say it "doesn't count" for some arbitrary purpose.
Except that wasn't the point? My point was that you can't consider Pyromancer anywhre close to the imaginary 5- 1X cycle because all the other see play in a variety of decks and their power is defined by their ability to go almost anywhere (see Confidant which goes in storm, aggro, and control, as well as SFM that goes in control and aggro, not as much in combo, or Goyf that goes literally everywhere) whereas pyromancer is bounded to one archetype. You could argue that snapcaster is sorta similar but snapcaster is still a way better card. So my point is that considering that, the imaginary 5-color cycle still miss the red card. One card being made great by the cantrip cartel doesn't make said card great in itself, pyro imho is just really good, but more than that, it's really narrow. The fun thing is that before monastery mentor was printed, Pyromancer was actually played as an alternative win condition for combo.
The actual problem with land destruction decks (and prison, and draw-go style permission, and oppressive discard) is that no matter what only one deck is actually playing the game. If the disruptive strategy works, the other deck is basically blank and the game is just that disruptive strategy playing out. When it doesn't work, the whole game is just the other deck doing its normal thing only a little slower than usual and the disruptive deck is basically blank instead. When WotC says they want to encourage interaction, they really mean encourage decks that have to take the opponent's specific strategy into account to win.
Except this isn't true at all? I never understood this argument. Some games may be blowouts where variance kill one of the player, but this is true of all formats no matter what because of the variance of the cards, but by the very definition prison decks always interact, they just slow down things.
Just take legacy eldrazis for example, which play 4 Chalices and 4 Thorns + Wastelands and is the closest thing to a prison deck in Legacy (you could argue land but lands is more of a control/combo with the ability to fetch tabernacle/chasm imho). If you play a deck like RUG delver, yeah, you get blown out by a chalice for 1. But that's not different from saying that beast tribal isn't viable in legacy for completely different reasons. On the other hand, 4-Color delver vs Eldrazis is one of the funniest and most interactive MU in legacy even after a chalice on 1 and especially so i'd say. Decay, Angler, Pyromancer that make tokens even under Chalice, Dismember that is castable for 1 even under chalice etc... you constantly play around said restriction and that make for an interesting game imho.
Heavy permission decks are unplayable when cards like vial and Cavern of Souls exist and are widely played, and the closest thing to it, Miracle, is still a deck with clear weaknesses that can be exploited. No game against miracle will ever feel uninteractive to you (sometimes even too interactive as they flashback and cast their fifth Swords to plowshares of the game)
Heavy discard is fringe playable with pox, for the simple reason that discard is inconsistent as it does nothing if topdecked, but were discard more prevalent, people would play more cards good against it (see for example wilt-lief liege in D&T as a tech vs Reality smasher) and it would become just another strategy.
Not even vintage shops is anymore all about locking out players permanently (after the cotv restriction) but more about slowing them down significantly and punishing them if they play certain kind of decks, while winning with threats that aren't slowed by your own prison pieces. Of course i don't think Vintage will ever be a "balanced" format by definition, but it's still an incredibly interactive format that is brought down by the swinginess of 1-ofs and the fact that threats are way better than answer in that format.
Also, just for information, legacy Eldrazi has basically already been hated out of the meta, with a lot of lands, loam and midrange bant-abzan decks going around. On the other hand, the fact that it was played a lot (especially for the cheapness) before essentally killed storm and canadian delver variants (RUG) which played only 1-cmc cards (except daze). Decks that will probably come back (especially storm) seeing how the current meta heavy on midrange and loam decks is extremely bad vs storm in general. The cycle of life i'd say.