That's simply not true. Vibrators don't really work that well if you somehow suppress the fantasies during use. Same way that GPT-4o works better if you fantasize briefly that it might love you when it says what it does. Almost all people who use it in this manner are fully aware of its limitations. While they are phrasing it as "I lost my love" their complaints are really of the kind of "my toy broke". And they find similar mitigation strategies for the problem, finding another toy, giving each other tips on how to use what's available.

As for the evolutionary perspective, evolution is not that simple. Gay people typically have way less offspring than vibrator users and somehow they are still around and plentiful.

Brains are messy hodgepodge of various subsystems. Clever primates found multitude of way how to mess with them to make life more bearable. So far the species continuous regardless.