Saying it's a "better" C++ is not very accurate. It's a very different beast IMO, and not suitable for all applications. There are areas where it shines, and areas where C++ would be a better choice.
If you want to call it 'C++-like' that's fine, there are similarities.
It’s hard for me to imagine starting a new project in C++ today instead of Rust, unless I needed interoperability with the pre-existing C++ ecosystem. What are some examples of areas where C++ is better?
There are other reasons, but having access to the mountain of existing C++ libraries (and C libraries) is no small thing.
The shear number of hours that can be saved by using existing known, well-understood, well-developed libraries and tools is enormous.
It will be another decade or two before Rust hits that point, if it does at all. It just takes time.
Also: Rust is a bit lower-level/aimed more at systems programming and forces thinking more about memory and structure than C++ does. That has advantages but isn't always great for higher-level applications. I can whip out a basic gui app using QT but that would takes ages in Rust.
> There are other reasons, but having access to the mountain of existing C++ libraries (and C libraries) is no small thing.
That's true. But a lot of code has a shelf life.
People used to point to CPAN as a huge benefit for using Perl. Most don't any more; while all that code is still out there, a lot of it doesn't really do much that's useful today. It was built for another time.
Some of the existing C/C++ code will rot in the same way.
I think code that is continually edited and expanded over many years, with lots of changes to requirements, if managed poorly, can have a shelf life.
But there's plenty of older code that will continue to work just fine essentially forever.
I use plenty of older code that hasn't been touched and is fine. I also use libraries that have been continually improved that have been fine. QT isn't perfect but it's been around since '95 and I think that the modern state of it is pretty great overall.
If you want to call it 'C++-like' that's fine, there are similarities.