I really think this argument is rooted in nostalgia. Alpha Centauri came out 17 years ago. Most people haven't played it in a decade. You can't compare it to modern standards, and it wouldn't have been such a good game if it was remade.
Most people haven't played it in a decade, but like I said, I still play it about once a year. The graphics are bad and the sound is terrible but the gameplay is still there.
It's possibly true that Beyond Earth is lacking in some of those things that you said were good about Alpha Centauri, but they're also lacking in Civ. Civ has no storyline or backstory, has characters and factions that all behave mostly the same (in fact, that's something that they're trying to address in Civ VI) and often doesn't have good diplomacy in the vanilla versions (and, like Civ usually does, BE improved on that in its first expansion). We forgive Civ for those things.
I couldn't really get into Civ5 so not going to comment on that. But I played and still play a lot of Civ 4, and in those games the factions and leaders do have personalities - not to the extent of SMAC, but you learn how different leaders will behave. You know Isabel will hate you if you have a different religion, you know Catherine will stab you in the back, you know Tokugawa will turtle, you know Montezuma will relentlessly attack you with stacks of cheap troops until one of you is dead.
BE on the other hand? What differences are there between the leaders? None that I can tell. They have minor different benefits, and they look different, and they have different colours, and er, that's it.
Perhaps you're too hard on BE and held it to too high of a standard (higher than even Civ, itself) so that you sabotaged your own enjoyment of it. I didn't compare it to AC--I compared it only to Civ V--and I enjoyed it and experienced that "one more turn" hook. I think that it's there, but, like any game, you have to be willing to find it. I mean, if you're letting things like the Supremacy path making you into a nerd with glasses, instead of a brain in a container, irritate you, you're probably not giving it the best chance to win you over
The nerd with glasses thing is just one of the countless examples of things that just weren't quite there. That's not why I didn't enjoy it, it's just one example. Take the lore. BE has some really great tech quotes - really great. Only problem is that they're all delivered in the same anodyne voice by the same woman. SMAC has all the different leaders delivering their memorable quotes - Yang telling us that the only point of life is life itself, Zhakarov telling us that not only does God play dice, but the dice are loaded, etc. Civ4 has Leonard Nimoy delivering them with great style. BE has some great lore buried away, but with no wonder videos, no one ever reads it.
Oh, and the wonders. Some of them are terrible - many. Most in fact. I'm looking at the info thinking "is this a wonder or a normal building?" No sense of awe, no fist pump that you beat your competition to a key strategic piece.
I think that you could make a really good remake, but updating it to modern standards would change it enough that some fans would complain that it doesn't resemble that 17-year-old game enough. Imagine if Civ V had been the first Civ game since Civ II. Some people would argue that it's not really Civ because it's too different. It has hexes, unstacked units, city-states, "Great Persons," a culture system, automated cities and so on. Because Civ evolved through III and IV and countless expansions, though, fan tastes and expectations evolved with the series. Alpha Centauri and expectations for it haven't evolved since 1999. A worthy successor to AC (which BE might be) might not be recognized as such because it would seem too different from what it's succeeding.
Well, the Civ5 argument, plenty of old time Civ fans argue that its not a true Civ game anyway!
However, I think the sales figures, and the amount of people
still playing it on Steam point to it's success. Like I said earlier, V isn't my cup of tea, but it clearly is a lot of other peoples and it brought a LOT of new gamers into the Civ world. And that's the thing - BE came out, and all these people playing Civ5 gave it a go and very quickly - like within a month - went back to Civ5. Most of these Civ5 players would never have played SMAC and would be too horrified by the graphics to even try. But they didn't like BE, and the people who did like SMAC, the people who still prefer IV to V, they didn't like BE either!
I remember about a year after release, just out of curiosity looking on Civfanatics to see which were the most popular forums. Civ5 was the most active by a country mile. But interestingly Civ4 - a 10 year old game - was also more active than BE.
If the new Civ5 fans don't like BE, and the old-timer Civ fans don't like BE, that only points to one thing - the game isn't very good.
It's a shame, because it could have been a great game - there's lots of good ideas in there, but they were all implemented so badly, or not implemented enough, that it just falls short in nearly every area.
Except the music. The music is epic.