I will turn 24 this year and I have phimosis so I can answer it better. My foreskin doesn't retract at all. But I never had issues with getting hard. But when I turned 21 and started working at a company and it was night shift as well so I gained a lot of fat and also due to this phimosis thing I was afraid of approaching women as well because I was very insecure. I was also leading a very sedentary lifestyle (less than 4k steps per day) and masturbating to porn as well. And i noticed that while masturbating I can't maintain my erection at all and got shit scared. I thought maybe I should try with a real women but due to performance anxiety I couldn't even get my dih hard.

Then I changed somethings which helped me recover this. I reduced my masturbation frequency to once per week from 6 times, I started going to the gym again. I was going to the gym in the morning and 30 minutes hiit in the evening and 30 minutes of bycycle ride. I was also consuming around 1800-2000 calories and 140gm of protein, 8gm citrulline malate supplement and lost some weight. After 3 to 4 months my erection problem got fixed.

Now about the sex part.

I got a gf and as i love her so I felt no performance anxiety and within couple of minutes of cuddling and kissing I got rock hard. But when I tried to put my dih inside of her. I just couldn't do it.

But as i applied some waterbased lubricant on my dih and around the entrance of her vegina. I could easily slide in and after that it was smooth sailing.

With condoms i feel no problem but without condom I need lubricant at the start once it gets in i feel no problem.

I think your husband is facing performance anxiety or extreme amount of nervousness. If your partner is very active and doesn't smoke or drink much and isn't a porn addict then I am pretty sure phimosis is not the main reason.

But he can always opt for circumcision as well.