I think the another Dan scam is a big factor

It is. Of all the big crypto persons I have heard commenting about Steem, only Hoskinson offered a somewhat neutral opinion, and stated that the network will have many hurdles to go over if they wish to hook users.

The others consider Steem to be a scam meant for the founders to earn more BTCs.

I also agree with the lack of marketing. A lot of it is what has been mentioned before: bunch of amateurs pretending to be professionals.

Maybe, there's just no reason to buy and stake Steem? Rewarding others, that's fucking stupid, right?

There isn't, in terms of ROI. Every vote you give to other people is at your detriment because it lowers your relative stake level. Hence, self-voting and burning became huge things.

There is no guarantee the post you voted on bring value to Steem down the road. But, I imagine that only matters more to whales.