I know its meaning. But I can't understand it in grammar. And does that means when it becomes an adage or 梗, we don't need to care about the grammar?
"美人只配(被)强者拥有" is a [(topic) + (comment/ opinion)] sentence.
(this phrase diminish the value of beauties)
It is not an adage
Topic: 美人 (beautiful women)
Comment: 只配被强者拥有 (only worthy of being owned by the strong ones)
美人 (beautiful women)
只配 (only worthy of)
强者(the strong one)
拥有 (to own)
The sentence above means "Beautiful women only deserve to be owned by the strong ones"
Substitute the topic and comment:
Topic: 木棒 (Wooden stick)
Comment: 只配給村民作武器 (only worthy of used as weapon by villagers)
Topic: :聖劍 (Holy sword)
Comment: 只有英雄才配揮舞 (only hero deserve to swing it)
"美人只配(被)强者拥有" is different from "只有强者才配拥有美人" (only the strong ones deserve to own beautiful women). Which is a [SVO] sentence
只有强者才配拥有美人 (only the strong ones deserve to own beautiful women)
(this phrase elevate the status of the strong ones)
[S] = 强者 (the strong ones)
[V] = 拥有 (own)
[O] = 美人 (beautiful women)
只有 ~ 才 ~ is a conjunction (only)
配 (worthy of) is an adverb for the verb 拥有 (own)
It is not an adage. It is a correct sentence.
配 originally means "match", derived for meaning "deserve".
Therefore, this sentence should be a passive sentence meaning: "Beauties should only be deserved by the strongs to own" (literally, word-to-word) or "Only the strongs deserve beauties" (native).
I have a different opinion about the sentence here. If you think deep, it doesn't seem to be logical. Usually, 只配 is used in a active voice, as in 你只配给我提鞋. Used in a passive is a bit odd in my opinion.
However, if I heard it, I would think it means the same as 只有强者才配拥有美人.