The c++ features that get bolted on to replicate those in other languages tend to never reach parity because of all the legacy baggage they need to design around. Modules are not nearly as useful as one would hope. std::variant and std::optional are not nearly as ergonomic or safe to use as rust equivalents. coroutines are not exactly what anyone really wanted. If you're simply looking for checkboxes on features then I suppose you have a point.

To be clear, I like and continue to use modern c++ daily, but I also use rust daily and you cannot really make a straight faced argument that c++ is catching up. I do think both languages offer a lot that higher languages like go and Python don't offer which is why I never venture into those languages, regardless of performance needs.

> std::variant and std::optional are not nearly as ergonomic or safe to use as rust equivalents.

> but I also use rust daily and you cannot really make a straight faced argument that c++ is catching up.

I mostly use std::ranges, lambdas, and concepts, and I see them catching up, as an evolutionary process rather than a fixed implementation in the current standard. Nowadays I can do familiar folds and parallel traversals that I couldn't do in the past without assuming third-party libraries. My optionals are empty vectors: it suits my algorithms and interfaces a lot, and I never liked `Maybe a` anyways (`Either errorOrDefault a` is so much better). I also use Haskell a lot, and I'm used to the idea that outside of my functional garden the industry's support for unions is hardly different to the support of 2-tuples of (<label>, <T>), so I don't mind the current state of std::variant either.

Everyone is welcome to their own opinions and there is definitely movement in the right direction. However, it's a far cry from catching up. std: variant doesn't force you to check the tag and doesn't have any easy way to exhaustively match on all types it stores. I'm not sure I understand what you're comparing it to I'm terms of tuples. Forcing everything to be "nullable" or have a default state can be painful to deal with and introduces invariants I often wish were impossible. Ranges are definitely nice compared to what we had before. I'm probably just not used to them, but they aren't always intuitive for me and spelling them is very verbose. It's not nearly as simple as calling map and filter on a collection or iterator.

There’s definitely holes, but I’m wondering what you are referring to here.