It is quite difficult to write idiomatic C++ without memory allocation, for one, which is often a requirement for embedded code or any high-availability code that is not allowed to have memory fragmentation.

Sure, it's possible (you can write C in C++, for the most part, and to its credit, C++ has placement new). But many of C++'s niceties require memory allocation, making much of its value-add over C questionable.

It super easy, we did it all the time back in the MS-DOS days.

right, but that was pre C++ niceties like the STL :).

C++ compilers shipped their own collections, for Borland compilers it was BIDS.

The first version used preprocessor macro tricks for generatic code, basically what Go folks re-discovered with //go:generate, we already had it in 1992.

BIDS 2.0 already used templates.

It was exactly because even C++ for MS-DOS provided safer library than C, that I was never that into C. It wasn't better than TP in features and safety, only in portability, and that I could get from C++ anyway.

That's fair! Perhaps I should amend to say that "current" idiomatic (almost got autocorrected to idiotic on my phone) c++ code is allocation heavy. Probably there exist suitable libraries I don't know about that basically implement the STL using predefined arenas for storage.