Ok first off OP you are coming to conclusions without any actual proof.
Lets not vaginas vary in size, tightness, depth, and how much they stretch as well as how much a woman is ok with it stretching in terms of sexual pleasure.
Everyone gets off on different things. As far as physical some women get off more through clitoral stimulation and other women penetration.
Some people want to be with someone they have a strong emotional connection and some prefer to sleep wirh complete strangers.
Anyways to assume guys who have large penises have it made is always the case because long story short not everyone's genitals are compatible.
I really can't speak for the female perspective other than what woman have said to me.
I will give one example, I dated a woman and sex with me was painful for her after a few minutes or less, she still came but I didn't because her being in pain wasn't something I was ok with but she was. Eventually after hearing her complain about pain from sex I just told her it wasn't going to work out. She persisted and asked why and I sai isn't it obvious our genitals are not compatible? She got it and didn't spend more than 30 seconds to reasoning to come to the same conclusion.
I have had much more extreme cases but I dont want to derail the thread but my point is sometimes people are willing to accomadate because they care about someone.
Insecurity is never flattering. Nothing ventured is nothing gained.
You can accept the fact you are human and everyone is different both mentally and physically.
So as far as who you end up with, it will be the quality of the love you make together. So that doesn't mean you will end up with someone ugly unless you are ugly too, genital size just means you have to find someone suitable for you and you suitable for her.
As far as being scared to have sex because of something you saw in the media or from looking at other mens genitals to size yourself up, that is on you.
If these cultural influences were not in your life or something you cared about would you still be scared to have sex?
I am not cicrumsised for example and sometimes the media portrays that as unlcean or my penis will reek and it only annoys me in the sense that I know someone will take it personally and not realize its entertainment.
I can assure you my penis is quite clean and here's something ironic most every woman I was with had no clue I wasn't cut until I told them and their typical reaction was "I expected it would be different" and it always was something from radio or tv.
I do remember one woman I dated and I were talking to a group of people and the topic came up and she said "I have never seen an uncut dick but I imagine it would be so disgusting" and I say that I wasn't cut and she says "oh I take that back, I guess its not like jokes on tv, I didn't even know but wow its really no different" and to add to the irony I had slept with another woman in the people conversing. They all just assumed from stuff on cartoon network's late night programs, comedy movies, and such.
Anyways radio and tv is entertainment and one person's opinion does not matter. There are 7 billion people on this planet and you only need to find one that likes you for what you are and have the feeling be mutual.
Look we all have had sex with someone and said to ourselves "well that wasn't very good, thought they would be better" and moved on. The idea that having sex with someone and them not wanting to be with you again kind of defeats the concept of dating until you find someone you really care for that cares for you.
So if you just go ahead and date sooner or later you will find someone that you are happy to be with.