I'm sorry, this is a straw man. It's not that people aren't intelligent enough to state what they don't like. It isn't that they hate all change or anything that's different. There are very specific complaints about this game. The fact that many people share them or some don't take the time to write a treatise about them doesn't make the criticism any less valid.
I've heard several different ratios for what is ideal in a sequel. Some hold to 1/3rd same, 1/3rd improved, 1/3rd new. Others use the 70% same 30% new. I think however you put it, Firaxis has pushed (and perhaps exceeded) the boundaries of those ratios in a way they haven't in quite some time. For some, this isn't a problem. But, for many, it is. Remember, Civilization 7 is not a game in a vacuum. The very name "Civilization 7" tells us that this game should build upon its predecessors and utilizes goodwill earned by previous entries to sell this one. There is a point where the number and degree of changes causes the connection to past entries to become strained or break altogether.
The fact that these same sorts of debates have been raging for six months shows that for many the identity of what the franchise is has been challenged by this entry.
What you're talking about isn't a straw man, I wouldn't say that, but it's definitely a kind of smokescreen. What I'm talking about isn't a strawman, people have complaints that fit within this categorization and meaningfully so. But there are other, qualitatively different complaints too. In social disagreements there's a tendency to assign sides and conflate all opinions with one or the other side depending on where they stand and that's just not accurate or precise.
Your very complaint in this case proves Firaxis's point. Disclaimer - they shipped an incomplete UI with a worse instruction manual. As far as the game goes, it mostly works IMO but some features are in need of major tweaking. But, IMO, nothing is fully broken, fully incomplete, or fully bad.
Civ 7 is qualitatively 33 33 33. It's just that qualitative change, though quantitatively balanced, can be disproportionately different due to the forest vs trees phenomenon. Civ 7 has the most excellent combat AI the series has ever had. The AI is not perfect or even ideal, but what it does is force you to make strategic choices and consider defensibility and make trade-offs. It retreats. It baits. It's hard to dislodge. No Civ game has ever had an AI like that. And we haven't yet seen the multiplayer meta when it comes to tactics. The game was clearly designed to emphasize tactics, since they have been broken in many previous games due to snowball. For me, 4 is the most specific example of a Civ game that leaned towards having to understand the meta to succeed. 3 is also very emphatic on understanding the optimized early game. 4 extends that past early. 5 is mixed, but through emphasis on tall and it's other major profound changes, it's own thing. 6 was loved in the end, but the midgame is a slog and late game is a joke. The entire point of 6 is to win before the late game.
I've noticed that 3 still has fanatics who disdain all that comes after it. Even though 4 stands as the sort of inflection point for an ideal Civ game, 3 has more loyal fanatics than 4. And then 5 has more loyal fanatics than 6. And ALL of them HATE 7, save a precious few who have engaged with it and get it.
7 is about big arrow strategy, then tactics. Add in the multi varied leaders and civs, and you have a framework for original choices for what the big arrows will be. It's a type of gameplay that no one has mastered, and very few have oriented to yet. And we assume adjustments will be made on the dev side too.
I will say it lacks a strong vibe that all civ games have, which is the fully open ended start where you conquer early game, then through experience optimize midgame, to snowball and be an uncontested god in the late game. This is a thing for a vast number of Civ fans. From a gameplay and game design perspective it's garbage, but that's what people show up for. This game prevents that cycle from ever being possible, which is why it will just not be for most.
However, a lot of people are not understanding basic mechanics and just rage quitting, sometimes from social pressure, and that's not right.
The AI, for example, is quite good in certain ways, at times. That's exciting. It means the concept is paying off. Still, it remains rare for the AI to properly employ their tactical options fully. Deity shouldn't just be about barb spam. It should just be about AI min/max genius. It should be the AI punishing you, humiliating you tactically and strategically. Right now the AI is "smarter" not "smart". There is a clever flow to 7's design. Air power is the final nail in the coffin which completely reorients the defensive and zerg rush strategies that apply to every era before. Ideally, the better air power will win. However, if air power is equally matched, here is where nukes are necessary. The AI is not forcing that outcome, so it's as of yet inadequate. But they could reasonably fix it. I don't imagine they will completely, but this iteration has come closest.