sudanglo:How many Esperantists would understand that to mean just mi and not aliaj?

Hard to say. Maybe Esperantists, in whose native language "se nur" doesn't mean figuratively the same as "mi deziras".

Germans could be candidates.

Falls nur ich es wüsste.
Literally: Se nur mi ĝin scius.
Meaning: If nobody except me knew it.

Wenn nur ich es wüsste.
Literally: Kiam nur mi ĝin scius.
Meaning: If nobody except me knew it.

Wenn ich es (doch) nur wüsste.
Literally: Kiam mi ĝin (ja) nur scius.
Meaning: I wish I knew.

So for Germans, sentences starting with "se nur" never express a wish.

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Spanish speakers could also be candidates.

Si solo yo lo supiera.
Literally: Se nur mi ĝin scius.
Meaning: If nobody except me knew it.

Si tan solo lo supiera.
Literally: Se tiom nur ĝin scius.
Meaning: I wish I knew.

Ojalá lo supiera.
Literally: Diovolante ĝin scius.
Meaning: I wish I knew.

Also in Spanish, sentences starting with "se nur (subjekto)" never express a wish.

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Now you might argue, that we are talking about Esperanto and not about other languages, but I think we are always slaves to our native language, and when we hear an Esperanto expression for the first time, we will most probably interpret it the same way as we would in our native language.