I wouldn't say it's about limitations as much as using a unique (relatively speaking) tool. These are tools with their own quirks and perks, that you have to master. It's not the limitations per se, but the path these limitations inspire you to take, and also as a result how the software running on the lo-bit machines are designed. Who would get the idea of adding tables or grooves like those on LSDj, to some generic PC software? Incidentally, those are two of the features that I miss the most in other software.
Generally speaking, I don't "get" the concept of using lo-bit VSTs on a PC. You keep the "worst" part of lo-bit (simple wave forms) and throw away the "best" parts (modulation, arpeggios, fine tuned control.) To me, composing lo-bit music doesn't take away something, it adds something.