But is that a problem of the language itself, or is it just a problem of available toolchains? E.g. if the gcc compiler collection would come with BASIC support and you just could type something like "gbasic -O3 foobar.bas -o foobar" to get a properly optimised executable out of your BASIC source code file then some may would still use BASIC today, I guess?
I started with BASIC too. Also enjoyed BlitzBasic2 for a long time on the Amiga. That's where I learned programming… back then when programming was still fun.
Which basic. I remember Atari BASIC - which was a terrible language since the organization was line numbers. Visual BASIC looked a lot nicer the few times I saw it, but I have a total of 10 minutes of my life looking at visual BASIC and so I have no clue how it is in the real world. I do know Visual BASIC was used by a lot of untrained programmers who never learned why we have best practices and so there is a lot of bad BASIC out there - this isn't the fault of the language just the users.
Realistically? No, not at all. The reason there are no toolchains for BASIC is because nobody uses BASIC (because it's not functional in our modern world), not the other way round.
Why do you think BASIC is not functional? Our modern world does not differ from the 1980 world at all. Variables are variables, subroutines are subroutines.
It fall out of fashion, along with Pascal, Perl, Ruby, but that's just fashion.
I have even seen pretty darn impressive things done with VisualBasic back in the day. And that were not hobby things. I've seen it used in very important mission critical telecommunication equipment. The compiler was custom, not the one from Microsoft. After all, the language had pretty much anything other languages had.
How can a language be "inefficient"? You can say it lacked on expressiveness. Maybe was too verbose? But I would not place BASIC into the "verbose" category.
Because BASIC simply doesn't have first-class functions, and they would be quite hard to represent in a BASIC-like syntax while keeping the language idiomatic. Even the unreasonably clunky C pattern of having a pointer to a function taking void* as its first argument (to account for closure captures) gets you a whole lot closer to functional programming than even the fanciest BASICs.
I started with BASIC too. Also enjoyed BlitzBasic2 for a long time on the Amiga. That's where I learned programming… back then when programming was still fun.