Is it just me, but I don't find npm that slow? Sure it's not a speed demon, but I rarely need to do npm install anyways so it's not a bottleneck for me.
For deploy, usually running the attached terraform script takes more time.
So while a speed increase is welcome, but I don't feel it gives me such a boost.
The speed shows up for large projects. Especially if you end up with multiple node_modules directories in your dev sandbox.