中文 - 中 = 丨 + 3 strokes
吴语 - 吴 = 口 + 4 strokes
文言 - 文 = 文 + 0 strokes
日本語 - 日 = 日 + 0 strokes
粵語 - 粵 = 米 + 7 strokes
For example, I have a book of 成语 stories that gives its table of contents in non-alphabetical order. (Since nobody understands the traditional ordering, I also have several such books that put their table of contents in alphabetical order.)
Here is the collation order in the book:
一 七 八 入 九 人 口 千 小 三 亡 大 不 专 天 井 见 毛 月 文 风 为 心 水 四 ...
Note that 三's radical is 一, the first Kangxi radical, and that 一 is listed first. Your theory is wrong. 三 isn't even first among the 3-stroke characters, which start (among these) with 口.
Why did you make up a false answer to this question?
I didn't say sorting is never done by stroke count alone. But I have seen radical+residual stroke count much more often than stroke count alone. Probably a result of the content I'm accessing. It's mostly Japanese and not intended for children.
The dictionary and non-dictionary sorting distinction that you make doesn't sound like a real thing. The audience, the country, and the number of items sorted are bigger factors. But you're not wrong in that stroke count is sometimes used alone.
I can't explain that because it's part of a different logical group, with its name written in a different script.† This puts it parallel to the Chinese options and to Korean.
> The Wikipedia sort for the languages is as I stated above
I took you to be describing the sort order for characters, not for wikipedia. Wikipedia doesn't obey that order either. You can check the page for Jiangsu, where all of the languages mentioned so far appear before the "Latin alphabet" style languages, but 閩南語 and 閩東語 appear after them.
† I also can't explain why wikipedia seems to have chosen 吴语 but 粵語, 客家語, and 贛語. Jiangsu is on the mainland... and so are Jiangxi and Guangdong.
> all of the languages mentioned so far appear before the "Latin alphabet"
> style languages, but 閩南語 and 閩東語 appear after them.