Interesting statement. I would like to agree with it. But in practice, is it workable?
For example, Cloudflare told me that if I would give them (or, to be precise, their robot) my primary Dreamhost panel password, then they could set up my Cloudflare account with much less hassle than me having to do it manually.
What do you do in such a case?
(What I did, through gritted teeth, was change my main DH password to something, tell that to Cloudflare, wait for them to finish, then change my main DH password again. Hassle. But probably less hassle than it would have been for me to set up my Cloudflare account manually.)