@Navelgazer I recall BE having some good gameplay ideas (as well as a beautiful game world and music), but the world building was so lackluster and shallow that I could never feel invested in it.
I didn't feel invested at all in BE. I really wanted to like it as SMAC is my favourite game in the pantheon. I think for me also the Civ V base didn't help. That's the only entry in the main Civ series so far which I couldn't enjoy...
I get this, especially being pretty familiar by now from these boards with what Zaarin is looking for in a Civ experience, and something like BE would likely never have the lore-immersion/RP aspects that you can get with a well-researched, well-designed CIv/Leader combo drawing from actual history (especially history that you know well or are curious about.) Apologies to Leucarum if this isn't what you mean by not feeling invested.
And BE/RT could have done better in this regard, though there are things I like about the lore and things I like less. In the plus column, having the different techs and affinity levels unlocking with quotes from the different Sponsor Leaders and key texts of different sorts from the fictionalized future (be they constitutions, academic journals, or folktale compendia) added a lot to the flavor, for me. Same with having to, for the most part, discover through playing what the Leaders' personalities and behaviors are going to be like. Arshia of Al Falah, for instance, has been the most loyal friend in every game I've played with her present as an NPC, and there's nothing stated outright that would make that seem like a given, nor does the lore say that Hutama of Polynesia is going to befriend you and backstab you later, though he usually will, and it makes sense. There's enough randomness thrown in that they don't play the same every game, but you learn what to likely expect, which is cool.
In the minus column, the lore and personalities are shallow, particularly in comparison with standard Civ games, if only because - again - those are drawing on actual history. The things that make the Leaders' personalities distinct also make them one-note (Suzanne Fielding talks in business-speak, Hutama's a schmoozer and a wheeler-dealer, Daoming Sochua puts everything in terms of analytical models, etc. And... that's it. That's the things about each of them.) Moreover, the text is riddled with typos and similar mistakes, which doesn't bother me terribly, but makes a lot of this aspect feel that much more rushed and under-thought.
BUT! If you're going down the rabbit hole with this (and spending time recently with the handful of other folks still keeping the lights on at the BE Forums on this site, I totally am), Firaxis seems to be setting the story in place that the Red Death (from the eponymous Civ6 scenario) = the "Great Mistake" that leads to the seeding in BE. With several games in development for 2021, it's possible that a BE successor is in the works. I don't see it as likely, but this would be a great chance to take what worked and improve on what didn't, because there's still a lot of meat on dem bones.