Dvorak is also based on English spelling, and thus its benefits vanish almost everywhere in the world. There are other alternative layouts, having the same kind of marginal gain over the standard, but then it's not available everywhere, and if you're a developer, you may also want an easier access to braces and stuff, and from here your keyboard will basically work nowhere unless you buy some kind of custom hardware…
The benefits don't vanish completely, since vowels are still the most common letters in most Latin-alphabet based languages.
Also "s" "t" and "n" are fairly-to-very common in damn near every language (Latin-alphabet or otherwise) due to how phonetics works. (They're the default-voiced-ness for each manner of articulation at the most-default-ish - alveolar - place of articulation for consonant phonemes.) The other two - "h" and "d" - are less universal, but still better than "j" and "g".