Under https://steampipe.io/docs/reference/config-files you put everything into ~/.steampipe I'm not a fan of random apps putting a random directory there. I prefer things to use the correct directory for the platform. Example https://specifications.freedesktop.org/basedir-spec/basedir-...
Ultimately we decided that the convenience for users and documentation of a single location outweighed the benefits of following the basedir spec, particularly when deployed across operating systems. We looked at other tools, including terraform [1], in reaching a final decision. FWIW, we do let you customize the location of the "install dir" [2].
Hopefully the benefits of Steampipe outweigh the "peeve" factor in this case <grin>
1 - https://www.terraform.io/docs/cli/config/config-file.html 2 - https://steampipe.io/docs/reference/env-vars#steampipe_insta...
Though admittedly, "convenience for users" is a rather tricky thing to define, as you really need to define "which users". I imagine ~/.projectname is easier getting started out, but the long term management is why we (try) to have standard locations for things.