The truth is that there are far more ways to have sexual pleasure without an erection than there are with an erection. And maintaining hot sex and intimacy over a lifetime requires more creativity and imagination than believing that one body part is required for either.
If you can’t imagine living with someone who can’t get an erection on demand (or however often you believe they should) then you’re not a very good match for someone who lives with ED. I need to point out that your dating pool is going to get narrower and narrower, if you aren’t able to expand your understanding of sexuality (and possibly gender), but that’s your cross to bear. For now, even though it will likely cause him a lot of pain in the moment, I think he’ll be better off finding someone who is open to participating in the search for hot sex and long lasting intimacy, and not just expecting it to happen.
If this sounds harsh it’s only because I am challenging some of the assumptions that underlie decisions like the one you’re making.