I doubt a home server centered around software like nextcloud would ever become commonplace. I think a more probable solution involves integrating new use cases with devices people already have, or at least familiar form factors. For example, streaming from your smart TV device (chromecast, Roku, Apple TV, the actual TV itself) instead of from the cloud, or file sync using one of these devices as an always-on server. But, in both of these cases, there is in inherit benefit from using a centralized cloud operator. What are the odds that you have already downloaded the episode to stream to your TV box, but not your phone if that was where you intended to watch it anyways? And for generic storage, cloud providers replicate that data for you in various locations to ensure higher redundancy and availability than what could be guaranteed simply from a home server or similar device. I presume new use cases will need to be more creative.