Apart from having Latin-like script I don't think there is much similarity between English and Vietnamese.
Either way, isn't Japan also famous for its engineering prowess? I doubt that country with such high engineering competency will lack talent for web development simply because of the language barrier (if there is actually the lack of talent at all). I'm not saying language barrier doesn't exist but if language barrier didn't prevent them from having companies like Konami, Square Enix, Namco, Bandai, Nintendo or Sony then why would it prevents them to have more web developers?
Either way, isn't Japan also famous for its engineering prowess? I doubt that country with such high engineering competency will lack talent for web development simply because of the language barrier (if there is actually the lack of talent at all). I'm not saying language barrier doesn't exist but if language barrier didn't prevent them from having companies like Konami, Square Enix, Namco, Bandai, Nintendo or Sony then why would it prevents them to have more web developers?
Ruby was created by a Japanese for that matter.