Its not too big of a deal there will be a wide range of clients to choose from with varying levels of centralization. Market will decide what the best approach is at any given time. Early on better ux will win, but they are not mutually exclusive and both styles will likely converge overtime on both sides. 

 Yes different topologies will always be possible but may become irrelevant if while nostr is still small and a big player takes the embrace, extend, extinguish approach.