OK, this one was tough to crack!
I almost gave up, but I believe I have found enough resources to help you grasp the concept of play.
What are the key ideas for white in this variation?
I think that you will find the answer you seek in this article. The second part is found here and contains relevant moves only-no additional explanations are added.
Haven't checked, but I would guess it is due to a combination of weaker players (the classical Scheveningen is not all that popular nowadays), most games being blitz or bullet and the move not being obvious.
While it might be the strongest move in the position, the maneuver Ne8, Bf6 is not obvious at first glance. It comes with some downsides which have to ...
I have not played this opening ever, and I am not qualified to answer it, I have not found many creditable sources for my answer, but I did manage to find a few.
I'm not a fan of copy pasting, so here's what I found
How Fearsome is the Keres Attack? By IM Mark Ginsburg
Sicilian Keres Attack: How to crush the Sicilian defence with the
Here is another game between GM Tukhaev - GM Nisipeanu (2012). After 7...e5, black loses control over d5 and f5, as well as exposing the a2-g8 diagonal for white's light squared bishop. Yet in a practical game, 7...e5 is fully playable. If you want to use it in your own games, my advice is to go ahead and use it as often as you can. The more you do, the ...
Sorry, not precisely a GM analysis of this line, but
I have found chessgames.com to be useful in this regard. Scroll down in the link, there may be some GM analysis in there. :)