I do think neopronouns can be confusing, but it takes literally no effort to use it.If you really must not use it you can just use singular they, or the person's name.
Both are social constructs.For example: the mammals class of animals is a social construct, While mammals would still have characteristics like being warm blooded, or not laying eggs, the classification wouldn't exist if people didn't invent it.Its also not a perfect classification, platypuses lay eggs but are still classified as mammals.
Sex is the same, its people who have certain hormones, certain chromosomes or certain genetailia, but there can be people who don't have the "Proper" chromosome / hormone for their sex, but they still are classified as male/female.
I think its important to look at what purpose a social construct serves, Mammals are a social construct, but they still serve a useful purpose (not saying sex/gender serves / doesn't serve a useful purpose).
Well, that problem also exists with mastodon.social and a lot of the actual fediverse.Its less decentralised, but its still distributed.