For me the biggest motivation to not dip my toes too much into BASIC on 8-bit computers was the abysmal performance. If I remember right, assembler was about 100x faster, compiled high-level languages like PASCAL about 10x faster, and FORTH somewhere inbetween compiled languages and assembler.
FORTH could've been a very elegant alternative to BASIC on 8-bit class hardware, but one major problem with it was that having to enter absolutely everything as RPN/postfix notation could be very unintuitive at times. E.g. prefix or mixfix notation for some things such as math is only very slightly harder to parse, but then provides a big gain in user friendliness. And floating point math takes up a big chunk of the code in typical BASIC ROMs, so it was clearly regarded as important to duplicate that desk calculator-like UX.
At least on the C64, I use BASIC as largely a scripting language and master scheduler, calling 6502 machine language subroutines with SYS, and reserving BASIC for the very highest level main loop or non-speed-sensitive tasks that would be inconvenient, bulky or unnecessary to write in assembly. It gives me a scaffold to hang things off.
Learning quickbasic which was compiled in DOS as a kid pushed me to learn x86 assembly just to make pixels appear on screen faster. Its slowness was a feature for me in the end.
