Pretty much. I just find it a bit harsh to call people dumbasses for using a sort of more correct term.
Not that I prefer pegacorn or anything, I only use the term alicorn myself: It wouldn't feel right using another term after Fallout Equestria. Lovely username, by the way.
ummm i have never heard of pegacorn or a unicus
i do believe its Alicorn could be all three though
i personally like Alicorn better because pegacorn and unicus sounds kinda stupid imo
...Celestia's an alicorn. And pegasi, unicorns, earth ponies and alicorns are all collectively known as ponies. Except Fluttershy - everyone knows she's a tree.