I said "meaningful conflicts," so you're strawmanning.
		
		
	 
No, you’re just being pedantic. There is no meaningful difference between the two phrases. 
	
		
	
	
		
		
			You're claiming it makes more sense to worship gods who want to destroy the world than gods who want to rule it.
The former is nonsensical, not the latter.
		
		
	 
The gods don’t have to be worshipped to exist, my dude. The only people worshipping Asmodeus are power hungry who don’t care what his ultimate goals are. 
Frankly it would make even more sense to just take the final step and 
not call them gods, but instead the setting takes the stance that they are gods because that is thier metaphysical nature, not because they are worshipped. worship of the betrayer gods isn’t widespread, they’re gods because that’s just what they are, regardless of worship. Which is much closer to a reasonable cosmology. 
	
		
	
	
		
		
			Also all the gods being usurpers was a really bad addition to the lore.
		
		
	 
No, it isn’t. The conflict that is basically the 4e Dawn War is a classic order vs chaos creation myth, expanded into the present day of the setting in its tangible effects. No other published D&D setting does that, or takes the evil gods and makes it murky why they are evil and if it’s even right to call them evil, which makes it possible to have cults that don’t actually believe that they are evil, while anyone who believes the mythology that the prime deities hand down as dogma does view them as evil in a way that means they would never worship them. 
That is a better setup than “Bhaal is Evil. Without any room for debate. He is objectively Evil and doesn’t pretend otherwise. His priests are Evil. His followers are…Evil. He has enough followers to be a powerful deity in this setting where divine power is relative to worship…because…reasons?”  
It makes it make sense that while the betrayers aren’t widely worshipped like the Primes, they do have cults that generally are either psycho annihilation cults (which exist irl so why wouldn’t they in a fantasy world?) and cults that view them differently from the mainstream view and don’t beleive that they do want to destroy everything. 
Hell IIRC some of the betrayers weren’t even in it because they want the world destroyed but because they had vendetta against one or more prime deity, or were trying to use the conflict to weaken the primes in order to take power from them. 
All of which is vastly more interesting in terms of reading a campaign book 
and in terms of running a game that uses the cosmological conflicts as the basis for the campaign conflicts, than the cosmos of FR.