There's still a ton of BASIC code being used and maintained today. Most of it by businesses. Back in the day (70s and 80s) the class of code was known as "Business BASIC"; tons of compilers and interpreters geared for business use were available on all computing platforms (IIRC, there's a version of BASIC for the Cray supercomputers of the day).
One very popular variant that's still sold and used today is/was known as the PICK system. It's based around a "multi-value" relational database structure (which is pretty cool all on its own - data is stored in "cubes" - rows, columns, then within each "cell" can be further dimensional data). It's main "claim to fame" was a certain level of interpreter compatibility - code from one vendor could be run on other vendor's products. PICK Basic compiled down to a bytecode which was run by an intermediate "interpreter", which was a kind of virtual machine. The bytecode looked a bit like assembler (and could be coded in directly if you really knew what you were doing). There were even a few companies that made hardware CPUs that could run the bytecode directly (instead of thru an interpreter VM). Think of it as Java before Java was a thing.
There also was (is?) one of the major industrial robot arm manufacturers who sold a version of BASIC geared toward programming their robot arms; I imagine that some of that is still out there running in the "wild".
One very popular variant that's still sold and used today is/was known as the PICK system. It's based around a "multi-value" relational database structure (which is pretty cool all on its own - data is stored in "cubes" - rows, columns, then within each "cell" can be further dimensional data). It's main "claim to fame" was a certain level of interpreter compatibility - code from one vendor could be run on other vendor's products. PICK Basic compiled down to a bytecode which was run by an intermediate "interpreter", which was a kind of virtual machine. The bytecode looked a bit like assembler (and could be coded in directly if you really knew what you were doing). There were even a few companies that made hardware CPUs that could run the bytecode directly (instead of thru an interpreter VM). Think of it as Java before Java was a thing.
There also was (is?) one of the major industrial robot arm manufacturers who sold a version of BASIC geared toward programming their robot arms; I imagine that some of that is still out there running in the "wild".