Oil pressure concerns, fact or myth

Ive always liked 20-30 psi at idle, but like stated 10 psi per 1000 rpm works well in most applications. My dart s 360, with a pressure fed lifter solid roller cam runs 35 at idle and exactly 60 above 2k rpm all the time.

To add, when I was working as an operator in a shipping yard some of the older equipment would pretty much make no oil pressure lol. The gauges that worked would read about 25 psi driving around and maybe 2 psi at idle. The gauge would barely read anything. These were big diesels (not sure the type) and because it was shift work they would run 24 hours a day! it was pretty much full throttle everywhere you went pulling 100k pound trailers. The one making the lower pressure had 24 thousand hours on it and it still ran perfect and had good power.

Not that I think thats good, it just shows that things can live with low pressure! LOL