At the lowest levels of power, you want to play expensive cards that actually can deal damage in scores or pile up resources in scores, because there aren't many cards that are capable of doing it at that level, and you are mostly playing normal creatures and stuff. Ramp is a favored strategy.

Then you go into the territory where it's a competition who can get more of those effects and more efficiently, so the name of the game are cheap cards with potential to give lots of utility through synergy with other cards and efficiency. Resource spiralling is a favored strategy.

Then you go into a territory of power where disrupting both bombs and resource engines becomes easier than creating them because boardwipes are cheap and counterspells and good removal are even cheaper. Control is a favored strategy.

Then you go into the territory of playing cheap and mathematically superefficient engines, cheap tutors, and fast mana, because the early game combos based on them can beat control even with very efficient answers by raw speed and reliability. Combo is a favored strategy.

That’s an interesting, succinct way of looking at it. Which of these do you prefer or lean towards? Then follow up question is, if you understand the unspoken social contract of your play group is “I will match the power tier of the deck you choose to play at this table” then what is your prefered power of deck?

I think that's a reasonable explanation of the progression of EDH deck construction.

Some of my former students started playing EDH with me and they were certainly still in the fourth tier, maybe creeping into the third. I'm firmly stuck in the second tier mostly because I lack the cards, desire, or temperament to play combo oriented decks. But I do creep into it on occasion (does Voltron count as tier 1?).

Seeing their reaction to me having answers to everything was really interesting. Some of the basic concepts of tutoring, silver bullets, redundancy (somewhat), etc. were a bit foreign to them. But it did make for some fun games. Gotta cherish those moments when you have a ridiculous yawgwin turn that they've never seen before.

What are the generals that usually fit into these tiers? I've been out of the game for so long I'm not up to speed on a lot of the new strats.

EDH is paradoxical because it's a primarily multiplayer format, which means that the stronger you are, the more likely you are to be perceived as a threat and ganged up on. There's no real way to optimize it because that one variable throws such a big wrench into everything.

Metagaming is perhaps more important in EDH than any other format.

here are the tiers of edh as I see them, they're ranked so that any deck of the next tier would often be oppressive in the preceding one

Tier 5: Trash
Decks only in technicality. Typically made by newer players without a firm grasp of the format and a lack of cards, and therefore features draft fodder any seasoned player would consider unplayable. In this meta, you don't actually win the game; your opponents lose.

Tier 4: Precon
Does not actually have to be a precon, could also be a budget player working towards a deck, or gimmicky theme decks. Categorized by having a semblance of overarching synergy, but lacking in overall card quality and consistency. These decks can often be exhausted of answers and get run over by value engines or other snowballing effects, and sometimes stumble on their own card quality and manabase considerations.

Tier 3: Curated
Well-rounded decks with consistent gameplans and purposefully chosen card inclusions, these decks are solid, but are often designed around being a certain type of deck more than actually winning the game, or are held back by budget considerations. They are often versatile enough to be able to handle a variety of situations, but lack the speed or density of answers to deal with decks that have a strongly defined gameplan.

Tier 2: Pubstomp
These decks intrinsically look a lot like the previous category, and to some extent they are, they just feature cards or strategies that are frowned upon in casual play. While they probably can't solo a tier 3 table on their own, they usually demand that the table does focus on shutting them down. Typically pack efficient combos or quickly snowballing strategies, but lack the infrastructure to fully exploit it.

Tier 1: cEDH
Gloves are off, at this point you exploit every aspect of the game and ignore any budget considerations with the sole point of winning. Dominated by fast mana and efficiency, every deck typically wins through a consistent combo-finisher, and either dedicates the rest of their deck to executing it as reliably as possible, or stopping their opponents from doing so.

Combo is always the best win-condition in edh, because it's easier to win than make 3 players lose. As you move down, you have a larger time window to execute your gameplan, but it's still fundamentally a game of either going under everyone's answer and finish the game before they can respond, or wait until they're exhausted and be the one that makes the last explosive play, the latter being more prominent in lower-tier circles.

I think combo is also disproportionately strong in EDH because it doesn't invite reaction as much as fairer strategies. If your plan is to get ahead on board and stomp face, you're going to have every opponent using their reactive cards against you because you're "winning", and anyone you attack will often trade creatures in blocking. On the other hand, if you don't seem to be "winning" until the turn you actually win, then everyone else will use their resources to fight the players that seem to be more ahead.

Combo in lowest-tier EDH is hard primarily because you don't have access to good combo pieces. Whatever you cook up will take a LOT of effort to find and deploy, will be fragile, and likely useless outside of the combo itself.
Combo in mid-low-tier EDH is hard primarily because you don't get as many unfair tutors, so the "100 card singleton" thing actually matters. Draw and card selection also lack in power to scour though 100-card decks fast.
Combo in mid-high-tier EDH is hard primarily because the tools for disrupting combos are, at this point, easier to use than tools for assembling them. At this point, cheap/free counterspells and combo hate enter the chat.
In the highest tier, because of good combo pieces AND cheap tutors AND fast mana, you can reliably search up and deploy a combo before your opponents can counterplay it.