SEO For Google : What Has Changed Over The Past Few Years

Off the top of my head, this is how SEO changed over the past few years:
Content quality: Google just expects better quality content, especially in English, than they did a few years ago. Google is way better at determining what better quality content than they were a just a few years ago. Of course, they sometimes get it wrong, which is why they continue to update their algorithms, to try to do better.
Less is more: Having fewer better pages is better than having many lower quality pages. This somewhat hit us with Panda but has grown and grown to be more of a thing over the years. Content pruning is a real thing, despite what some say.
Links: Both algorithmically and manually, Google is discounting links that are not all that great in a better way. It just isn't as easy as joining a link farm or PBN and rank high in a matter of days.
User experience: It just seems sites with cooler and easier UX are doing better these days.
Competition: There are more web pages out there competition for the same keywords than a few years ago, so which will Google rank number one?
Google UI changes: Of course, we got things like featured snippets, different ad placement, voice search, and new user interface changes at Google. These all play a role on the traffic you'd get from Google....

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