This, with respect (okay, with minimal respect) is nonsense. The Real World is full of all sorts of names and naming customs. And, frankly, as a complaint, it's riddled with entitlement. I, the reader, want everything to be easy for me and familiar to me. I don't want to face difference. It's scary.
Bollocks to that. Language -- language in its widest sense, meaning all those wonderful, contradictory, baffling, eloquent, elegant, fluid, magical, changeable, ways in which we communicate and miscommunicate with one another -- is one of our greatest gifts and challenges and tools. Languages are rich and nuanced and redolent and textured. Language is one of our greatest adventures.
And I, for one, want to go on those adventures. I don't want to read about worlds that are exactly like mine, to see only my own practices and expectations and ideas mirrored. I want to be shocked and scared, challenged and surprised, baffled, frustrated, delighted, awakened, expanded. I want to learn.
And I don't learn in a landscape where everyone is limited by one set of rules, where it's only 'realistic' for characters to be called Boyon and Girla (or, for daring writing, Boyol and Girlie). That isn't the world I live in now, for heaven's sake.
Reality check. Not everyone has a name like Bob or Sue. Even within my own white British culture, I know or know of Elizabeths and Bartholemews, Susannahs and Benedicts, Annabels and Julians. Not all of them are Liz or Bart, Sue or Ben, Anne or Jules, either. And if we lift those cultural blinkers, the wider world has and uses proudly, happily, longer names every single day. Saraswati. Paradorn. Ssima Be-Ping. Hideyoshi. Hitomi. Bronislav. Go and look at Thai names, or Indian ones, or even Irish. Conchubhair. Mael-Sechlainn. Derbhorgaill. We are not all white and Germanic. We are not all uniform, nor should we be.
And I won't fit my characters with the strait-jacket of lazy (culturally privileged?) reader expectation. Most of the names I use derive from Old French, Middle English and Welsh. Some of those are short -- Aude, Jehan. Some of them aren't -- Thiercelin, Gracielis.
Name vary, people. Names and naming conventions differ with time, with culture. Some times and cultures allow for abbreviations or pet names -- Thierry, Sue, Pinky. Some add syllables to indicate intimacy or respect -- Ryouga-kun, Mo-Colum. My characters don't live in a world defined by my junior school, which was in a white-bread small village. They don't have to end with the suffixes that make my culture-mates feel comforted. They aren't me. They aren't Jane-from-Basingstoke or Jack-from-Poughkeepsie, either. If I want to read about Jane and Jack, Ill buy a book set in those sort of places. If I find Jane in Fantasyland, her writer needs to convince me that Jane is a natural fit in that place -- and that that place is real in itself and not just Basingstoke with dragons. (Actually, Basingstoke with dragons might be an improvement. But you know what I mean.)
When William Morris made his translations of Old Norse sagas, he adapted the female names he found in them so that they ended in -a, enforcing Latin grammatical practice and (in part) naming practices on 12th century Scandinavia. It looks and sounds wrong. Like 19th century contemporaries who, following the fashion for Anglo-Saxon revivals, gave their daughters Old English names (Ethelberta), he was blinkered by his own cultural expectations.
Fantasy needs to be bigger than that. So, don't go telling me I have to stick to Boyon and Girla. This world I write about is not the world right outside your door. The Real World is bigger than your street. And so should fantasy be.