Genuine question, how to prostate massagers help with ED?

I'm getting of a certain age where I'm getting targeted with a lot of ads for ED treatments (thankfully I'm not at the point where I need them, yet). One of the ads I get a lot, especially on Reddit, is for what appears to be a vibrating prostate massager. I get how that can be pleasurable, but I don't know how that specifically helps get an erection if you're otherwise physically able to get one.

Am I just missing something?