if porn causes ED in real life sexual situations, shouldn't I still be able to get hard to porn?

It doesn't make sense to me that I wouldn't be able to get hard to porn anymore. Isn't porn supposed to make it so we have unrealistic expectations and we can't get erections with real girls? Why can I not even get hard with porn even anymore if I am very turned on? Went to a urologist and he tested my blood and said I have no problems and this will pass.