I can not repro this:
Windows:
julia> @time_imports using GR
13.0 ms Preferences
...
46.5 ms GR 7.82% compilation time
WSL:
julia> @time_imports using GR
12.1 ms Preferences
...
39.0 ms GR 6.57% compilation time
Can you try clear out .julia/compiled
, do a re-precompile and check again.