And it wasn't hard to achieve. The idea was to use length delimited strings rather than 0 terminated. This meant that slices of strings being strings is a superpower. No more did one have to constantly allocate memory for a slice, and then keep track of that memory.
Length-delimited also super speeded string manipulation. One no longer had to scan a string to find its length. This is a big deal for memory caching.
Static strings are length delimited too, but also have a 0 at the end, which makes it easy to pass string literals to C functions like printf. And, of course, you can append a 0 to a string anytime.
One of the fun things about Empire is one isn't out to save humanity, but to conquer! Hahahaha.
BTW, one of my friends is using ClodCode to generate an Empire clone by feeding it the manual. Lots of fun!
The latter two (hash maps and vectors), though, are just compound data types that can be built on top of standard C. All it would need is to agree on a new common library, more modern than the one designed in the 70s.
Hash maps are mostly only important because everyone ought to standardize on a way of hashing keys.
But I suppose they can both be “bring your own”… to me it’s more that these types are so fundamental and so “table stakes” that having one base implementation of them guaranteed by the language’s standard lib is important.