Dapps such as dtube and dlive target video producers and gamers. If you are willing to expose yourself publicly over a decentralized network, then the dapps will reward you for your content.
I don't see those dapps attracting writers, users, or viewers to the Steem platform. I understand viewers are currently not being paid to watch YTube videos, but Steem is marketing itself to be a place where you get paid for your voice/quality content. So as a user/viewer, how would I get paid to be a stable user of the Steem blockchain when it is the video producer that is reaping the rewards? DTube viewers do receive a small reward for watching, but I believe the curation reward is also dependent on stake. Not much for small fishes. I would imagine the mass mentality (having earned pennies for being on Steem) would simply switch back to YTube where there are no issues with connectivity and they have a broader selection of topics to watch.
Although @steemmonsters is not a dapp, I feel the project has a lot to offer to the Steem blockchain. Steemmonsters is a card collectible game, but a community formed where users of different interests are welcomed and supported. There are writers, artists, musicians, developers, video producers, and of course, gamers. We all have different interests but our interests intersected with steemmonsters. A community of different userbase should be supported, imo.