Not only can it be killed but it will be killed. Every giant social media outlet / app / company or what-ever else that has had great success eventually is left in dust by the next big thing.
Hotmail / Messenger / Friendster / Myspace / LiveJournal
The list goes on. ..... Facebook and Twitter will be next. We are on the cusp of the next big thing and its Steemit or another site like it.
My question is what would happen if they also come out with tokens and start sharing the rewards with its users?
They need to adapt or be left behind. The thing is with big companies that are use to getting 100 % of the rewards is that they likely are not going to want to share the pie. I have read rumors months ago of Facebook creating its own token / coin. The rumor was circulating around the same time they stopped advertising crypto.