It’s been debated for many years, but Google says that content inside of an accordion or tab on your site will get just as much credit as other text on the page. This article from Search Engine Roundtable gets further into Google’s thoughts on this.
Google has been personalizing search results for roughly a decade, but they’re not personalized nearly as much as you think. You can read more about this over at this article on Search Engine Land.
Having a fast-loading site is a good thing. Users like it and Google likes it. While there’s no official guideline, Google says that a page should download in <100ms. Read more about John’s tweet and some other discussion about this over on this post at Search Engine Roundtable.
It makes sense, and Google has confirmed that if your site requires cookies in order to view content, Google won’t index that content. You can learn more about how Google handles sites with cookies at this post from Search Engine Roundtable.