  Gender-neutral pronouns have recently been introduced in many languages to a)
include non-binary people and b) as a generic singular. Recent results from
psycholinguistics suggest that gender-neutral pronouns (in Swedish) are not
associated with human processing difficulties. This, we show, is in sharp
contrast with automated processing. We show that gender-neutral pronouns in
Danish, English, and Swedish are associated with higher perplexity, more
dispersed attention patterns, and worse downstream performance. We argue that
such conservativity in language models may limit widespread adoption of
gender-neutral pronouns and must therefore be resolved.
