Of course she's popular. She's the EmoGoth chick. Oh, and the only non-evil god with pretty much ANY characterization or development past a bare cardboard cutout. Her lore, by virtue of *existing*, is naturally the most engaging and exciting.
Whereas, yeah, most of my ideas about, say, 4e Corellon I stole from 1e-3e's Corellon Larethian, an only vaguely compatible god who doesn't outside of some shallow surface similarities have much of anything in common with 4e's Corellon. As far as we know. Maybe they're exactly alike other than an alignment change(And gods know most of what little is written about him makes him sound like he wants to be Chaotic Good but can't because it doesn't exist anymore). We'd never know at this point.
Gods help me if I wanted to worship Avandra. Or Melora. Or Sehanine.
I honestly can't even NAME all of the PHB gods, because most of them are so undeveloped and generic there's nothing to remember about them.
But I'm cranky and I hate the Raven Queen and I'm sick to death of hearing about her, which is a major cause of hating her. OK, we get it, DEATH. Sehanine Moonbow was a cooler death god(CG death gods for the win), and I didn't even care for her that much.