C++ introduces a shit-ton of stuff that one often doesn't want, and even Bjarne Stroustrup (who many content has never seen a language feature he didn't want) has been a little alarmed at the sheer mass of cruft being crammed into recent updates to the standard. I know many C++ people think C++ is pure improvement over C in all contexts and manners, but it's not. It's different, and there are features implemented in C++ and not in C that could be added to C without damaging C's particular areas of greatest value, and many other features in C++ that would be pretty bad for some of C's most important use cases.

C shouldn't turn into C++, or even C++ Lite™, but it shouldn't remain strictly unchanging for all eternity, either. It should just always strive to be a better C, conservatively, because its niche is one where conservative advancement is important.

Some way to adopt programming practices that guaranteee consistent management of array and pointer length -- not just write code to check it, but actually guarantee it -- would, I think, perfectly fit the needs of conservative advancement suitable to C's most important niche(s). It may not take the form of a Rust-like "fat pointer". It may just be the ability to tell the compiler to enforce a particular constraint for relationships between specific struct fields/members (as someone else in this discussion suggested), in a backward-compatible manner such that the exact same code would compile in an older-standard compiler -- a very conservative approach that should, in fact, solve the problem as well as "fat pointers".

There are ways to get the actually important upgrades without recreating C++.

> if you want a dialect of C with arrays that know their length, you can use C++

C++ doesn't have arrays which know their length.