The Lightning Network will be ready soon, which will handle that amount of transactions.

Bitshares, Steem(it), Ripple etc all are variations of the almost 20 years old Paxos algorithm and could have existed well before Bitcoin. So why now?

Technically, using "master nodes" or "witnesses" has not much to do with Satoshi's innovation, which is complete trustlessness. I'm not saying that Paxos-based consensus systems don't have their use cases, but it's just not the same category.