nprofile1qy2hwumn8ghj7un9d3shjtnddaehgu3wwp6kyqpqe8da6pzqppy8sksszk8q5t469u765m2y2678pryavhg5f09fw36s57hcpm (nprofile…hcpm) It's. A couple years ago I was teaching a lisp course in a summer school (and was using guix+rde for setting up a dev environment) and guix pull almost screwed up the first day of practice. The speed of initial guix pull is an area, where guix can be improved a lot.
https://lalambda.school/
The good thing is that consequent runs of guix pull are usually much faster, so most of the time it doesn't hit that hard (and this is also probably one of the reasons why this doesn't get fixed).