The pace it is going at, it’s not that far from it
Those kind of comments are not based on looking at Rust's features on a theoretical level.
It's more from the viewpoint of "How hard is it to get something (correctly) done". Those impressions are mostly formed either from using the language and failing (or having severe difficulties) to solve a given problem, or being exposed to blog posts describing those kinds of problems.
Rust sure does not have as many features as C++, but it seems that in practice, the combination of available features (and/or the problems those create) is perceived as just as complex as C++. Though not being a fair assessment, the Rust community will have to try fighting this perception, if Rust is not to be labeled way more complex than C++ in the coming years.
I don't know if you are using Rust, but what would you say, why is that? Where does that motivation come from?
It is always comforting to dismiss something that you haven't made much effort to understand as unnecessarily overcomplex. I think we're all guilty of that at times.
On the other hand, maybe those folks decided, after giving it a serious try, it's not worth it. Mind you, that does not mean they are right. But in the end, if the effort for those people is perceived as too high, then maybe, just maybe, in practice it really is.
After more than 25 years as a developer, I learned the hard way, that programming languages, are, in the end, a matter of taste. You won't get someone to use a language, just by citing the feature list. Programming languages are a product made for developers. If they don't like it (for whatever reasons, and yes, these are at times highly subjective) they won't use it.
If I really like C and I ship a bunch of C code that gets exploited to build a botnet, that decision had consequences. I should have valued safety higher and the fact I didn't "like" safe alternatives was a distraction.