Back on Steemit, why the change?

So I left Steemit and Dtube a few months back because of the changes that took place. They changed the way people could upvote and basically made it impossible to like anything. I left when I uploaded a video and could not upvote my video or upvote others due to not having enough power. I haden't even upvoted anything in hours. I was cut off from offering upvotes and comments. I have come back to see what has changed and to see if it has gotten better or worse since I left.
What has changed?