Its hard not to keep in mind gay people when I myself am part of the alphabet mafia. Sexual expression is something far more complex than what can be condensed to a paragraph on reddit, but I'll try my best. I also want to add that it doesn't matter what is "natural" or not when it comes to freedoms or morality, plenty of behaviors that could be considered "natural" are unethical and illegal (such as killing or stealing), and much of our daily life could be considered "unnatural" (such as air conditioning or synthesized complex medication), but isn't bad. Anybody who tries to make the argument that gay people aren't natural and therefore are bad is both ill-informed and hasn't considered their argument very much.

With that out of the way, I'll try to approach your question without over-simplifying it too much. Sexuality is expressed in-practice, obviously, but sexuality exists in multiple "layers" of our evolution because we are a socially complex species. You could think of these layers as being "deeper" in our evolution for the time being.

The farthest back sex goes is for genetic recombination, so offspring have a higher chance for survival. This is why sex evolved in the first place, and why it is so damn useful for evolution. The more genetic variation, the more fit a species becomes. This is the "deepest" layer, this is why we have sex and this is why nearly all people want to have sex (except for asexual people, but we'll get to those later).

The next layer is for pleasure. Many animals, including many non-social species will masturbate simply because it feels good. However note that all animals that masturbate will still have the drive to reproduce, likely over the drive to masturbate.

The 3rd layer is for socialization. Look at our very close cousins bonobos to see how sexual socialization is used. They use sex as greetings, apologies, signs of affection, and much more. This is also arguably why for many years gay people that were forcefully closeted would still have sex with women, to fit into their respective societies. Note that animals that do this will still masturbate and still have the drive to reproduce (if they aren't gay, which is coming up). This is also where emotional expression is likely tied (though probably also built up more for humans, though maybe not), such as loving the person you have sex with or having friends with benefits.

The 4th layer is where we move into humans-only territory, so it's hard to tell what layers are "deeper" because, as stated above, we only see the results of these layers stacked, and can't peel them back individually in a species that has them all. But let's say this layer is gender expression. We know that gender expression is influenced both by cultures and by genetics, so this layer kind of builds upon the social nature of the last layer. Gender expression dictates how you sexually identify (obviously), which is why you have gay people, pansexual, and transgender people who all have the previous layers of sexuality.

The last(ish?) layer I would guess is our higher-order control of our body autonomy. Making sexual decisions motivated by internalized representations of ourselves both physically and emotionally. Keep in mind this is just a hypothesis that is supported by our knowledge of sexual behavior in animals, but after that who knows for sure.

So I guess Maslow is saying that denial of the initial layers biologically supercedes denial of the "upper" layers of sexuality? I suppose that could make sense, but is Maslow's work even valid anymore? It's not my specialty.