Most bioinformaticians use Linux, if not all. If they use Windows they most likely heavily use WSL for their work. So Seq not working on Windows isn't a pressing issue (albeit Nim's support for platforms is a big boon).
Seq lowers the bar for starting bioinformaticians and provides a drop-in replacement for Python. Nim is a lot more mature and it's awesome, but I think Seq(or Python/Julia for that matter) vs Nim boils down on how easy it is to jump into the data science/processing ecosystem of the programming language. Julia is going strong in this regard and Nim is catching up thanks to wonderful work being done!
