Perhaps people from RStudio will have a better answer, but I do seem to remember that there was a plan to pre-compile most common packages (e.g., tidyverse) so that installing them would take a minute instead of 20.
That being said, if you are an instructor, you can create a base project that your students will start from and where all of the packages that might be needed are already installed. Of course, for pedagogical reasons you might leave one or two packages not installed and install them during the class, but at least students won't need to wait for too long.