In 90% of the cases, grammatical gender has nothing to do with male/female qualities. It should be enough proof to point out the fact that there are multiple words that are almost perfect synonyms and are of different genders:
Silla (f.) y asiento (m.)
Gafas (f.) y anteojos (m.)
Cara (f.) y rostro (m.)
Computadora (f.) y ordenador (m.)
Obviously, those words don’t differ in their male/female qualities. They mean almost the same thing and are interchangeable in numerous contexts, so how could one be masculine and the other feminine? Another example would be words that change their gender after adding a suffix:
Cabeza (f.) y cabezón (m.)
Furgón (m.) y furgoneta (f.)
Tecla (f.) y teclado (m.)
Cuerno (m.) y cornamenta (f.)
Again, if someone feels “tecla” sounds feminine for some reason, I don’t think the fact the word becomes masculine after adding a suffix will change that. And what about words that have changed gender over the course of history? An example is sangre (blood), which was masculine in Latin and is still masculine in other Romance languages such as French sang, Italian sangue or Portuguese sangue. Was Spanish blood not manly enough? I don’t think so.
So grammatical gender has little to do with male/female qualities, except for a couple of cases:
- When a word can be inflected for both genders1, most of the time the grammatical gender it takes determines its natural gender: chico/chica, profesor/profesora, corredor/corredora, etc.
- With animals for which there are different names for the male and the female animal, each of them generally agrees with their natural gender: vaca/toro, carnero/oveja, caballo/yegua. The same applies to some family members (mamá/papá, madrina/padrino, yerno/suegra), and some other words. These are called heterónimos.
Now, you’re asking if grammatical gender can affect subconsciously the way we regard different words. I think there’s no way to tell, and unless someone carries out a well-thought experiment or can link one, all we can do is sheer speculation. Bur sincerely I really, really doubt grammatical gender can affect the “manliness/girlishness” of a word. If I say “Pepe es una buena persona” no one would feel Pepe is somewhat more feminine because I used the word “persona”. And if I say “Sofía es un sujeto en mi experimento” Sofia hasn’t become masculine because I said “sujeto”. So there is a link between the grammatical gender and the natural gender of a word that is patent in some cases, but that doesn't affect most words, and treating masculine words as male words and feminine words as female words would be to make a distinction that just isn't justified and that, as far as anyone can know, no native speaker does.
1: This is generally truth for animate objects. Some inanimate objects can be inflected for both grammatical genders too but that doesn't affect their perception as masculine/feminine: charco (m.) and charca (f.), farol (m.) and farola (f.), or cesto (m.) and cesta (f.) are some examples. For more on this topic, see Meseguer, Á. G. (2002). El español, una lengua no sexista. Estudios de lingüística del español, (16), 8.
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