I have to agree with @andrarchy here. Steem + smart contracts would just be a worse EOS. Steem is an application-specific blockchain. It's like an ASIC miner vs a GPU miner - GPU miners (Ethereum/EOS/etc) can be made to do anything, but they will never be as good or efficient at the one specific task of an ASIC miner (Steem).
Yes, it means that Steem Monsters cannot be a truly decentralized application (though it can be come surprisingly close using the methods currently available), but it also means that it will be the overwhelming best option for services trying to monetize/reward content publishers online in a decentralized manner.
I think this can be summed up with a quote (I don't remember who said it):
Do one thing and do it well
Great points, the ASIC miner analogy is perfect.
Not totally sure who originally said "Do one thing and do it well", but I believe that's the UNIX philosophy / mantra, isn't it?