Spanish is a gendered language. All nouns are either masculine or feminine. So are the adjectives referring to those nouns. Why this should be so is not clear, but many languages are gendered, including Latin, from which Spanish evolved. I've studied French, and the way it handles gender is very similar to Spanish. My guess is that both languages conjugate verbs similarly, and without some way to alternate the ending sound of the nouns speech would sound monotonous and repetitive. There are no neutral nouns.

I have no idea where 'Latinx' came from. No doubt from some feminist woke linguist, desperate to show how unsexist they were. In Spanish, masculine nouns usually end in an 'o', and feminine ones with an 'a'. Nouns are also preceded by the definite article 'the', el or la (there are a few exceptions, such as the words for 'map' and 'hand': el mapa and la mano.) The plurals of el and la are los and las.

The default term for items of unclear gender is always the masculine 'o'. For example, if you're talking about 'the citizens', both male and female, you default to the male, as in los ciudadanos. If you are specifically referring to women citizens only, its las ciudadanas.

Gender has nothing to do with the properties or characteristics of the object involved. It is strictly random, and probably historic. For example, the word for pistol is la pistola. The word for revolver is el revolver.