What's your long term perspective on the platform?

I don't have one. I have a long term hope though.

Why would you say that most have quit the platform?

Mostly due to the price continuous fall and lack of success with their blog. Sometimes you can appreciate having lots of comments to your posts but almost no rewards but you can't have that forever. It is a rewards based "social media thing" though. Especially when you see/have seen that much circle jerking and boosted posts and so on.

What would it take to get rid of the bots/auto-votes?

Bid bots problem already solved. You can't buy upvotes from them anymore. At least the ones that I am aware of. Auto votes, I don't know but I would take this feature out asap, if you wanna have a "live platform" and encourage as many people as possible to be active and why not even invest in Steem from their own money.