It looks like you're making two points: it's weird that a shortened name would be another word, and it's weird that the name is so long and unpronounceable. The answer to both? It's not that weird.

This recent thread is somewhat relevant to the first question. It's kind of a mess cause there's no real answer, but the general idea is "No, it's not weird to have a name that's a word; it happens all the time, even in English." I call my friend Grace "Grace" and don't think anything of it. Sure, if you're name's April or May, you might get some jokes during "your time of the year." The name has a distinct cognitive connection to the idea of the person.

As for it being an "awkward name," that's largely because you speak English, not Egyptian. Now, we can't be entirely sure just what Egyptian sounded like, so let's use a modern analogy. For example: I study Mayan languages. The word for "red" in K'iche' Mayan is kaq. The verb "to throw" is k'aq. The adjective "new" is k'ak'. The guava fruit is "kaq'*. The difference between these words does not exist in English phonemes. "K" is like our "k," but "q" is further back on the palette, but not quite the Scottish "ch." The apostrophe indicates a glottal stop, where you stop the air before continuing the word. (Imagine a British person saying "Beatles" or "bottle"- the "t" becomes a glottal stop.) Having studied the language, I can usually hear the difference. But if you haven't, it takes a few weeks of classes to reliably distinguish "k" and "q." Now, imagine that with a bygone language which nobody's spoken aloud for centuries and we're really not sure about how exactly vowels were represented. You're gonna end up with some "funny" names.

I should add that lots of non-royal folks had the same sort of awkward names. A random selection: "Ankhsheshonq," "Hekanakhte."

Even to a native speaker, those names would have been too long for everyday use. Or were they?

And then there's "Ay," proving that some Egyptians did have pronounceable names.