This is a fun topic! I feel like it's a Rorschach test for how people understand the game.
tl;dr Ramp exists because some people want to do the thing, but faster, so faster ramp will always be more desirable to them. Everyone else plays ramp to the degree that they still want to win sometimes, but no one actually
has to if it's not fun for them or they don't need it.
To specifically address your questions:
1. Do we think (the best) ramp is good? Everyone runs ramp, and so far as I can tell the accepted wisdom is that it's the best thing to do. The most competitive decks in the format use large amounts of ramp and, even at non-cEDH tables, the ability to explode early and achieve an unassailable lead requires ramp. I certainly cannot imagine doing the most powerful things decks can do without more than the normal one mana per turn. No, ramp is not sufficient to win, but I would argue that it is necessary. So I am arguing for yes on this one, but willing to be challenged.
I don't think the question can really be whether it's "good" on its own. No ramp is necessary to cast all the big EDH spells if you are willing to wait. You are guaranteed to eventually hit your max power if you live long enough. The reason people ramp is because the game has a timer they can't wait for: the game ends when one player locks in their wincon. You don't ramp so you can cast spells; you ramp so you can cast spells sooner than your opponents. If you play against slower decks, then you have more freedom to play slower. If you play against fast decks, then you need to be fast in order to win. Most people try to play as fast as possible because we don't know the speed of the deck we're playing against. If Deck 1 is playing 5
Manalith variants and Deck 2 is a direct copy but with the Manaliths swapped for
Sol Ring,
Arcane Signet,
Mana Vault, etc., Deck 2 is probably going to win because it does the same thing but sooner (that's just going to be a reality in a game where some cards are better than others - better cards will win). But if Deck 1 has no ramp and instead has more redundant cards for their strategy, then there really is a trade-off in choosing how much ramp to include. Deck 1 would be gambling that a greater density of useful cards will outweigh a slower average start, and Deck 2 would be gambling that they will hit only enough ramp to act sooner without replacing useful card draws with useless ramp.
2. If 1. is true, and ramp is so good to be ubiquitous, is that a problem? My proposition (something to be discussed) is that, actually, EDH would be better without it. These spells take up slots in the deck, introduce (unneeded and possibly excessive/unhealthy) variance, and don't really add anything to the game. If it were tuned to the point where it were more of a balanced trade-off, such that some decks would want and run ramp but others might put in none at all, would the format be more interesting? It would also likely be slower, which I propose is also no bad thing.
I think you are making an unfounded logical
leap here. Saying it is good is not the same as agreeing that it is ubiquitous, and something being ubiquitous does not make it a problem. You say EDH would be better without it, but it sounds like you mean it would be slower without it, and slower is somehow better. The issues that you mentioned, deck slots and variance, seem like strange issues since this entire format is designed with 40 extra card slots and is singleton to
increase variance. This is the lots-of-cards-high-variance format. I guess I would suggest that creating a high-variance format where these cards are legal is the whole point of EDH. So to say that they are bad for the format makes me
wonder if maybe it's the format itself that is the issue.
Don't get me wrong. I hate how fast the game is nowadays. I like my games to take an hour or more, and all my games are definitely faster now than they were, say, 10 years ago. I don't really like the standardization of decks that comes when people feel like they have to include the same suite of good ramp in every deck, and I agree that it would be a lot more fun, casual, and janky if we had more room for niche cards. But that's also all my own fault because I'm trying to win as well as have fun. There is no authority that forces me to play fast except the knowledge that another player might. The reason EDH has become more "solved" is because we are all actively trying to solve it against each other. If you aren't playing a big 8-drop Elder Dragon with a three-color upkeep cost because you know you'll lose before you ever cast it, then you've already made choices to play smarter to win the game. Observing that one strategy will typically
defeat another strategy is not the same as being forced to adopt that strategy. Only a desire to win does that. I remember Sheldon's main argument against fast mana boiled down to "I don't want to play fast mana and I lose to people who play it, but I would also like to win, so can people not play it and let me win". And the response that will always get is, "No,
I want to win so I'm going to", which is why we will always be in this position. (Side story: last night I cut
Nissa, Who Shakes the World for
Woodland Druid in my Seton deck and it made me feel ruthless. I am not immune to
lure of fast mana.)
As for ramp being a balanced trade off with some decks wanting it and others not, I would say that's already the case. I think we're in agreement that ubiquity is not quality, so the fact that everyone runs
Sol Ring doesn't mean every deck benefits optimally from running it. My
Nicol Bolas has 9 pieces of ramp, including
Mana Vault,
Sol Ring, and
Arcane Signet, and every one of them hurts because it's taking a slot away from another fun giant sorcery. My
Tuya Bearclaw, which wins a lot more often, has 2 ramp cards (
Domri, Anarch of Bolas and
Caravan Vigil) because there is a trade-off between drawing mana versus useful cards, and she tops out at 3 cmc and wants the cards. I've never felt that deck needed a
Sol Ring.
It sounds like you are saying that fast mana puts restrictions and pressures on deckbuilding that aren't fun, and I think a lot of people would agree. In the end I don't quite understand why it should be a conversation about whether the whole idea of ramp as a game mechanic is good. Certainly the variance and restrictions caused by ramp are nowhere near the variance and wasted slots caused by the land/mana system in general, right? It seems like, if anything, the ramp strategy exists primarily to smooth out the effects of that design choice.