I missed those discussions, now I'm curious why you feel that way. Can you elaborate (or link)?
Sure - it means there are essentially too many identical copies of most things, so nothing really matters.
- there's not enough variety in the system generation (types of government, economy, station, etc.) to stop systems being really interchangeable. Everything has tens if not hundreds of copies, so none of them exactly matter
- so for example the Thargoids at their greatest reach had captured 200 inhabited systems, and if you didn't happen to visit there, you'd never know (but if they'd attacked at "yes, this is actually a credible threat rather than something which might wipe out humanity long after all of ED's current players have died in real life" rates, it'd have had the opposite problem of spreading the human players across incomprehensibly many fronts at once and making their actual presence largely optional). It would have taken literal years - in the absence of any human defence - for the Thargoids to capture a system that anyone much had heard of before
- a few exceptions aside, the players-per-system count is basically "one" or more usually "zero", which means that a lot of things don't quite work:
--- obviously if you're into meeting people, you usually don't
--- but it also means that commodity markets tend towards "boring" because you'll often be the only one using them. Weirdness like CMM Composite recently aside
--- and similarly BGS states and influence really aren't all that dynamic because a lot of systems don't have enough people acting in them to keep it moving
- on the Powerplay side, you get a similar issue to with the Thargoid War: powers don't really benefit from having more systems once they get above a critical threshold (which they're all well above), and there's plenty of spares, so there's no incentive for conflict in what should be the Official Competitive Bit
- basically all the multiplayer bits don't have critical density of players ... but it's also clearly gratuitously big for singleplayer stuff (FE2 had about 1000 systems - the smallest of the four for inhabited space - and I doubt many players visited all of them, either)
One of the particular things I look for in this sort of game is a "sense of place" [1]. Elite Dangerous is pretty good at that in terms of the distinction between the bubble, and deep space, and Colonia, and the smaller outlying colonies. But within the bubble, everything basically blurs together to be a homogenous mass. It's not helped by the distinctions between Imperial and Federal space, or Democratic and Feudal government, or Grom or Mahon influence being fairly subtle - but even accounting for those, it's all pretty samey.
Colonia has the same components, but with only 70 systems to build from them, each of them feels a lot more distinctive. And it has a higher (well, maybe not this week) player/system count than the bubble, so you occasionally see other players, and the markets and BGS states are all a lot more volatile.
About 1000 systems would - with hindsight - get about the same player/system ratio as Colonia in the main bubble. You still wouldn't necessarily see many other players except in the very busiest systems, but you'd see the
effects of their passing through much more. Powers would have 30-100 systems each, so would really need to fight each other if they wanted more. A Thargoid invasion taking out 200 systems would be an absolute crisis, not a "call me in a couple of decades if they're still here" event where the (story-level, I'm sure the actual fights were fun!) excitement has to be added artificially.
The thing is, I'm pretty sure the Frontier-of-2014 never gave the slightest bit of thought to sizing the bubble to likely player numbers or future story options or anything like that. It's the size it is because this is a sequel to FFE, so Sol, Achenar and Alioth need to be superpower capitals, and the sphere of inhabited space needs to be sized around that. Which, now that it's a
sphere rather than FE2/FFE's circle, and now that the LY distances between those three are set to their real-world values, makes it about 150-200 LY radius.
Having decided (I doubt it was ever really considered an option!) not to fix the issues arising by using the Thargoids to compress the bubble to 1000 systems, then going the other way and saying sure, why not let every player have their own system or ten has some appeal to it. That itself gives a certain sense of place, in a different way.
[1] In terms of the obvious competitors, I'd say No Mans Sky aggressively rejects the concept, and X4 does it extremely well (though not in a way that ED could replicate the specifics of, of course!).