(Feel like i should add in at the “title” that i am not non-binary but i am Brazilian so take what i say with a grain of salt, se você for também do Brasil e estiver lendo isso ahco que seria legal você adicionar o que pensa também, especialmente se você for membro da comunidade LGBTQ+)
The biggest problem with the word is because it’s how it’s written, Latinx is simply considered wrong in Romance Languages.
But it is anglicized, Latinx was created by the Americans which makes a very big problem as since it was created in the United States, Latinx ends up following the English grammar (which is a Germanic language) and have different rules compared to the two main languages used in Latin America which are Spanish and Portuguêse which are Romance languages and that don’t use gender-neutral as English speakers do.
Portuguêse pretty much gendered almost the entire vocabulary (including non-living things), for instance instead of using “The” we use “O” or “A” which ends up gendering words to male and female respectively, ironically it also genders the word “Pessoa” known in English as “Person” to feminine being written as “A Pessoa” but despite all of what I mentioned, Person still remains gender-neutral and the words being gendered works more as a phonetical thing (which can basically be explained as “we wrote and speak this way because it sounds nicer than saying this word in another way”) and we still have Inclusive Language which is used to include words and try making sentences inclusive to everyone without discriminating a group and not interfering with the language rules.
There is also a pretty big problem with Non-Binarys in Brazil is that their pronouns are still having problems with the authority that regulates the Portuguêse language which is the Brazilian Academy of Letters because since the pronouns end up written in a way that don’t follow Portuguêse grammar rules with the consequences of many linguists considering non-binary pronouns wrong (The government also deems Non-binary pronouns wrong and made some regulations to make schools to not teach about non-binary language but they don’t stop schools from explaining and teaching about inclusive language and they also don’t stop you from legally changing your gender to “Other” and being nonbinary)
And don’t get me started on the linguist variations, accents, and regionalism on each region in Brazil that are very different from
each other and which each region have their own linguistic identity as for instance we have :
*Carioca
*Baiano
*Sulista
*Gáucho
*Mineiro
And by the way, these are only some of them and only Sulista can be actually translated which means Southern while translating the others would either change the meaning (Mineiro literally means miner but in this context I mean the regional culture) or simply would be untranslatable, now try to fit in non-binary pronouns (it’s going to either be very difficult or simply not going to happen)
Besides like I mentioned before, non-binaries are still having trouble trying to adapt words to make them gender-neutral and also follow Portuguêse grammar rules correctly, then the Americans created Latinx with some of them trying to force it down to another language they know nothing about and having a very different language structure compared to English, so trying to make Latin Americans say Latinx against their own will is Ignorant, Arrogant, and also Cultural Imperialism, but if you didn’t force it them to starting saying it and they decide to say Latinx with their own free will, then it’s still a bit Ignorant and Arrogant since you are giving an opinion on how a Language should change despite not knowing anything about it.
In either case, Portuguêse and Romance languages in general simply don’t work well with non-binary pronouns and words (at least currently), so saying Latinx in Latin American countries ends up being wrong and also bringing the chance of alienating people against non-binaries and making more problems against the Non-binary discourse for inclusion.