> IMHO pluralization is a prime example, with an API that only cleanly handles the English case

That’s not true at all? Gettext is functionally limited to source code being English (or alike). It handles all translation languages just fine, and competently so.

What is doesn’t have is MessageFormat’s gender selectors (useful) or formatting (arguably not really, strays from translations to locales and is better solvable with placeholders and locale-aware formatting code).

> fully in the translator's hands.

That is a problem that gettext doesn’t suffer from. You can’t reasonably expect translators to write correct DSL expressions.

> Gettext is functionally limited to source code being English (or alike). It handles all translation languages just fine, and competently so.

The *ngettext() family of functions take two strings (typically singular/plural) and rely on a language-wide expression to choose the variant (possibly more than 2 variants). There's no good reason for taking two strings, this should be handled in the language file, even without a DSL. Ngettext handling a single countable makes some corner-cases awkward, like gendering a group with possibly mixed-gender elements. The Plural-Forms expression not being per-message means that for example even in English "none/one/many foo" has to be handled in code, and that a language with only a rare 3rd plural has to pay the complexity for all cases.

Arguably, those are all nitpicks, Gettext is adequate for most projects. But quality translations get cumbersome very quickly.

> You can’t reasonably expect translators to write correct DSL expressions.

This feels demeaning. Translators regularly have to check the source code, and often write templates, they're well able for a DSL like MessageFormat's, especially when it's always the same expressions for their language. It saves a trip to the bugtracker to get developers to massage their code into something translatable. You can't reasonably expect a English-speaking developer armed with ngettext to know (and prepare their code for) the subtleties of Gaelic numerals.