This sort of difference of perspectives is why we see the same trends in our wealth distribution, in how our economy is functioning, etc. debated with one side saying "It's interference in the free market that's the problem" and "It's the free market that's the root of the problem". There's points usually for each side and each individual decides which facts they think are the most compelling.
It's part of why so many larger initiatives are hard to move forward.
I mean... the most current example is the differences over masking... not just for any dispute of fact (which there may be or not)... but because anything that becomes politicized removes rational discourse and results in identify being challenged instead simply of views. This leads to divides that are not bridgeable because for either side to move, they'd have to then change some part of their identity and notion of self and possibly accept that some of what they hold emotionally tight is in fact not a fact but an error or at best one of several reasonable alternative views.
I suspect when we move from thinking 'I voted for a conservative/liberal/anarchist/etc' to 'I am a conservative/liberal/anarchist/etc' then one moves to a space where you tend to need to support everything that movement says or else that threatens sense of self/identity, whereas if you just voted for someone in one election, then you could just as easily vote for someone else next time.
The ZS was probably showing its age in some ways and probably had some strong points (stability, function). Any long running empire will fall eventually as far as past experience tells us. That's not to say that everyone would rush to embrace the new thing which might seem worse or more chaotic than the old way (however it may be failing bit at a time). Much of the time, the people in an empire don't see the end coming until it literally is upon them.
The Terrans weren't any more effective at stopping massive collapses, nor was the merged Vilani/Terran Imperium.