I dont have enough knowledge here to give an answer, sorry.
Is there no difference between the two on your old machine?
GUI WSL is unlikely to happen anytime soon. What is more likely and would have the same effect is Rstudio on Windows running with R in WSL. Your other option is running rstudio server in WSL (How to use RStudio Server for Ubuntu on Windows 10 | by Francesco Piccinelli | Lead and Paper | Medium).
This thread is relevant to this discussion: Large Cmdstan performance differences Windows vs. Linux