I don't know for Japanese as meaning sometimes shifts from Chinese, but in Chinese the standard definition of 可 is "can, may, be able to".
You obviously learn it by itself but as Chinese words are mostly a combination of 2 characters, you immediately also have to learn e.g. 可以 (can, may, be able to), 可能 (maybe), 可爱 (cute) etc.
So someone who's learning characters in order to get 90% coverage (or whatever) would not simply learn characters but learn actual words. Learning characters in isolation would not be that helpful, indeed.
When you don't know a word (i.e. a combination) but you know the individual characters it is much easier to learn the new word either by guessing or checking.
In context, the meaning of 可爱 would be fairly straightforward to guess, for example. Even in English 'lovable' is a synonym of 'cute'.
> the meaning of 可爱 would be fairly straightforward to guess
To be honest this whole thread about 可愛い is more or less bonkers, because it's an ateji. The word's meaning doesn't derive from the characters, the characters got arbitrarily attached to an existing word because they were similar in sound and meaning.
As such, the whole thing is about as meaningful as talking about how easy it is to guess that 珈琲 means "coffee"...
I must say I don't know much about ateji in Japanese.
In this case, though it does seem that the characters where chosen at least partly because of their actual meaning.
It seems that it is both an ateji and a jukujikun [1] because the word does not come from the characters but the characters do have the correct meaning.
The characters of 可愛い do not have the “correct” meaning. Just like in Chinese, 可 means “can”, or “possible”, and 可愛い is a weird exception. (It’s also nearly always written in hiragana.)
Nearly every word involving the kanji 可 in Japanese has something to do with permission: impossible (不可能), possible (可能), permission (許可), approval (可決), etc.
That said, the kanji-centric view of the world is ineffective, and one primarily adopted by beginner learners who have not spent any significant amount of time studying words in Japanese. It is always better to just learn words.
> the characters where chosen at least partly because of their actual meaning
Sure, didn't I say they were in my post?
The point was, in a discussion of how well X predicts Y, it's not very useful to examine a test case where Y came first and X was chosen post-hoc to match it.
It does not seem arbitrary in this case because the meaning does match.
I do take your point that using that word in the discussion above, which is about Japanese was not the best example. On the other hand, it is a good example in chinese.
(A) In Japanese the meanings don't match that closely. The word didn't originally mean cute, but rather pathetic or pitiable, and evolved over time. More info: http://gogen-allguide.com/ka/kawaii.html
(B) By arbitrary here I mean that there is no linguistic connection. "Arbitrarily chosen because they are similar" => "chosen for no reason other than their similarity".
You obviously learn it by itself but as Chinese words are mostly a combination of 2 characters, you immediately also have to learn e.g. 可以 (can, may, be able to), 可能 (maybe), 可爱 (cute) etc.
So someone who's learning characters in order to get 90% coverage (or whatever) would not simply learn characters but learn actual words. Learning characters in isolation would not be that helpful, indeed.
When you don't know a word (i.e. a combination) but you know the individual characters it is much easier to learn the new word either by guessing or checking.
In context, the meaning of 可爱 would be fairly straightforward to guess, for example. Even in English 'lovable' is a synonym of 'cute'.