I disagree. Many (probably most) makefiles conform to the GNU Coding Standards, which recommend declaring "all" to be the default make target. `make all` does not install; that's what `make install` is for.
The idea of the original parent comment on Make is not about well conforming makefiles.
The idea is that if one doesn't trust a random curl-ed install file, they shouldn't trust a downloaded makefile either -- and for the same reasons, yet tons of people complaint about the first, but have been using the latter for decades without complain...
https://www.gnu.org/prep/standards/html_node/Standard-Target...