If all you're interested in is initial sex, it's only a problem if you insist on "mating" with someone who is more attractive than yourself and/or insist on them doing the asking.
If you take the initiative, and you can put up with a little bit of stumbling and embarassment, then no, it's incredibly easy.
If you're talking about longer term relationships, it gets more complex.
There are so many women (not so many men) who complain about how tough it is to be beautiful, and they are SO full of BS. If it was so tough, they could give themselves a big old makeup scar or a pillow in the gut that appeared to add a few pounds and ... poof ... the problem would go away. Doors would stop opening themselves. Drinks would all of a sudden cost money, etc.
On the other hand, there are people who are beautiful, know they are beautiful, realize that it is only one aspect of their lives, know they are lucky with respect to THAT ASPECT of their lives, and don't try to pretend otherwise. Alas, they are few, and far between.
Really beautiful people who expect the world to come to them - yeah, they are going to be disappointed. A LOT of the people who DO come to them are not who they're going to want to end up with.
SMART beautiful people, sooner or later, figure that out and actually realize that anything worthwhile, even relationships with people who base part of their mating ritual on attraction, require EFFORT.
There are a lot of people (both beautiful and not) who simply don't put in the effort, go from one relationship to the next and then decades later, realize that they never ended up with anything meaningful and don't understand why.
You get out what you put in. In the case of beautiful people, the beauty is not something you're "putting in" - it's just there. It's not something you're adding for free. It's not something that's going to come out of the other side of the equation in your benefit (unclear how it effects the other person).
The ONLY thing it does, in the long run, is make it easier to START a relationship. It is far easier for you to pick a person and say "I want to get to know that person better" and actually do it if you are beautiful than if you are ugly. It opens doors.
Once the door is open, the more time that passes, the less the beauty will keep it open and the more you need to depend on other things like kindness, charm, witt, actually being a worthwhile human being, to keep it open.
It does add one element that makes life more difficult: Really beautiful people will tend to get "hit on" continuously. There will be lots of temptation, and consequently their partners are constantly put in the situation of potential jealousy.
They DO have something to be jealous about, though, don't they? Really beautiful people will have lots of potential offers, and having more offers, they are statistically more likely to take one or more of them. If you can, somehow, assure your partner that you aren't going anywhere, you're golden, but that's tough.
And yes, jealousy does break up relationships. Realistically, it breaks up more relationships between people where one (or both) of the partners is particularly beautiful than when both are in the realm of the mortals.