I am not afraid of it, nor do I hold negative feelings towards it.
If you have a partner and she is not a wanna-be renunciate too there is no urgent reason to stop sexual activity. If you quit this one out of a billion pleasures that bring us dopamine you will still have the others to quit, like the mind wandering in search of pleasant sensations and avoiding negative ones. It would be bad to cut off this pleasure from the list depriving another human been of it too. Only thing you can do is get advanced in meditation and cut off more from the attachment to sensual pleasures overall.
However you seem to be a bit too aggressive on this subject, almost encoureging it but a particular kind of agression. The one that springs from seen too many people using the fact that they've quited sex for narcissistic supply and been way more radical against it than you are pro (pro in a particular context). Quiting sex is a huge source of narcissistic supply and as you can read in "The broken Buddha" it is kinda the one and only justification of those bad monks for been superior. Only 1% of the people are narcissist but 100% of people have more or less narcissistic traits been something needed for survival.
Been a narcissist who have quited sexual activity and not been a meditation master yet I can confirm you that this is a very big and special source of narcissistic supply for the next reasons:
1. Althow very easy to quit compared to any other medium/high pleasures, probably the easiest, it makes you feel "special", a thing that every narcissist wants. It makes you feel special because the other people think it is so hard that they do not even think it is possible and you try to lie that to yourself too.
2. Narcissist are a lot more asexual than normal people from the begining. Narcissist despise sex because anybody can have it, not only the "special" ones. Even a mentally retarded can have sex. That is why sex is considered too mundane for a special person like the narcissist.
3. Narcissist are misogins and love to sexually frustrate woman by refusing sex. After I quited sexual activity I found how big this pleasure really is and try to avoid it. (I also have great tips) If I would not be a budhist and be the most convinced hedonist of all I would give up sex for this reason alone.
4. It makes the narcissist less dependent on the world, something that he want's a lot too.
So keep in mind that the overreactions from the people who have quited it may cause the same need to overreact in you. Why do you think that there are so many people that from all pleasures have quited sex on this forum if not because of the narcissistic traits in all of us?
PS: I have to add that quiting sexual activity has a lot of big practical advantages that few know of witch I am gona enumerate if anybody is interested. If I would be a convinced hedonist right now trying to get as much pleasure as posible in this life I would for sure quit sexual activity with other people and keep only masturbation on my list.