I hope you are right. People try to conflate nostr and bitcoin growth and I cannot see it at all. I always look for the incentives, every aspect of Bitcoin provides positive incentives to human greed. I do not see those incentives for running a relay. The profit/risk ratio does not seem (to me) enough of a driving force for an ever growing number of relays. I hope I am wrong. 

 There are incentives for those who run them . Ecash mint operators would run relays. Businesse and creators on nostr would. Specialized Clients looking to provide unique experiences for their users would also run relays