I'm an old-timer. I don't like fancy new things. Tau - fine, stay on your side and do whatever it is you do. Necrons - fine, Chaos Androids reworked, no issue there.
Remove the Squats - nah, I like them. And as the fluff around them "all getting eaten by nids end of story full stop" makes no sense to me, I just ignore it (see 5th Ed Squat codex in the Lost and Damned-board)
Remove Eldar Harlequins, Exodites and Pirates - but I like them. They stay.
Enter C'tan, and muck up all teh fluff - not really intersted, as the consistent fluff was out the window.
Then there are some minor blurbs, Isha "might" be alive, Marines inventing a craftworld and blowing it up, the Dark Eldar fighting with Chaos to topple the Black Library, Ghaz calling it a "draw" on Armageddon, and so on. Just leave it be, as it makes too little sense to worry about.