Let's look at this in a little more detail: some historical and some bot. My sources are GoGoD Winter 2019 edition and LZ #254.
This fuseki with the immediate approach answered by the 2-space low pincer has a long history but it is not correct that it was popular at the time of this game. If we search GoGoD we find a total of 85 games stretching from 1647 to 1933. It was, however, mainly a tool of the Yasui family and the main source of 17th century games are biased toward the more famous Honinbos. In the 85 games, 50 featured a player as Black with "Yasui" in their name and 53 featured a "Honinbo" as White. The "Page from Go History" article in Go World #11 is about Dosaku and the superiority of his fuseki theory over that of his rivals of the time. The featured game starts with this 1-2-3. All of these games occurred in the 16th and early 17th centuries.
The last game with a Yasui player as Black appeared in 1722. GoGoD has only 8 games later than 1722. Interestingly, four of those games featured the Yamamoto Genkichi that we see here, two as Black in 1801 (including this one) and two as White in 1809 and 1813.
During the battles of the 17th century, the 2-space low pincer was replaced by the 3-space low pincer where Black responds immediately to White 2, probably due to Dosaku's influence. This is interesting because LZ calculates a nearly identical winrate for Black (at lower visits the 2-space is preferred but the calculated difference falls to only 0.1% better beyond ~100K visits).
Also interesting is what happens when Black responds to White 2 by playing elsewhere. The human preferred play was the 5-3 point at P3 in the lower right, facing the lower left corner. LZ calculates Blue as the upper left star point (D16) instead. However, there is a problem with this analysis. P3 in the lower right does not appear in LZ's policy net. As a result, even with 200K visits LZ had only 9 visits at P3. So should we conclude that D16 is "better"?
Of course the analysis here is more about the joseki rather than the fuseki and indeed the joseki appears far more often than the specific fuseki in this game. If we search GoGoD on an otherwise empty 10x10 corner, we have 167 games with the 1-2-3-"tenuki"-5 of this analysis. White more often replied to the attachment than not, but playing elsewhere was a significant choice at least temporarily. In terms of local responses the two main variations are what is discussed in this analysis: the wedge at D4 played in this game and the outside hane at F4 that Elf "preferred". Both plays first appear in the 1660's in GoGoD.
The outside hane goes back to 1660. The intent when it was played by humans was to trade the outside for the corner. It anticipates the cut by Black and then a series of ataris that ends with White capturing Black's original 3-4 stone.
- Click Here To Show Diagram Code
[go]$$W Joseki part 1
$$
$$| . . . , . . . . . ,
$$| . . . . . . . . . .
$$| . . . . . . . . . .
$$| . . . . . . . . . .
$$| . . . . 7 . . . . .
$$| . . . 5 4 8 . . . .
$$| . . X 3 X O . . . ,
$$| . . 9 6 O X 1 X . .
$$| . . . . . 2 . . . .
$$| . . . . . . . . . .
$$+ - - - - - - - - - -[/go]
Play continues to
below and then Black plays elsewhere
- Click Here To Show Diagram Code
[go]$$B Joseki part 2
$$
$$| . . . , . . . . . ,
$$| . . . . . . . . . .
$$| . . . . . . . . . .
$$| . 6 . 5 . . . . . .
$$| . . . 3 O . . . . .
$$| . . 2 O X X . . . .
$$| . 4 X O X O . . . ,
$$| . . O X O X O X . .
$$| . . . . 1 X . . . .
$$| . . . . . . . . . .
$$+ - - - - - - - - - -[/go]
Elf chooses a very different variation. The stand that it uses after the first atari does not appear in GoGoD. When we try in LZ, it calculates Blue as the same stand at F5 as Elf. OK let's write that up - the humans are wrong again. Alternatively let's just... wait a while. Two choices dominate LZ's policy net, the stand at F5 and the atari at D4. Its initial calculations do not cover anything else. However, at around 50K visits it has a first peek at the strange-looking alternative of hane at H4. Then at around 130K LZ calculates H4 in more detail. If you have a really fast machine (or in my case if I go and have dinner and then watch a little TV), LZ calculates Blue as shown below given enough visits.
With a million visits LZ calculates a main line as shown below. There are two interesting things here IMHO. First, this variation uses the same corner maneuver by White as the human joseki to take the lower left corner. The difference is that interpolating H4 and the other moves near it leaves more potential on the bottom side. Second, watching the calculated variations rolling out in Lizzie, the bottom left corner (up to White 15 shown in the picture) is stable relatively quickly (by ~160K visits). Thereafter, out to 800K is almost entirely about the rest of the board.
_________________
Dave Sigaty"Short-lived are both the praiser and the praised, and rememberer and the remembered..."
- Marcus Aurelius; Meditations, VIII 21
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jlt
is not on AlphaGo Teach either.
The last weekend before coming back to the US I went to a go weekend at a resort. The highlight on the last day was a game between Takagawa and Takemiya. Ishida Yoshio gave the running commentary. There was time to kill while the players got several moves ahead. Ishida warmed up the room. He was very good at it. (If you don't know, he is also a professional jazz guitarist. He used to perform solo at jazz coffee shops and kissaten in Tokyo.) At one point he asked who had come the farthest to be there. I raised my hand, which got a big laugh from the audience. "So it seems," said Ishida, and then said, "No, really. Who came the farthest to be here?" I was not amused.
and 
had been popular for over a century, but are minor errors, according to Elf. Either may be OK sans komi, OC. 
.
- 
are joseki. 
seems natural, but does not appear in Waltheri.
and 
push through. Then 
and 
confine White to the corner.
encloses the top right corner. Then 
- 
play a joseki that is popular with the bots.
stone. 
occupy the open corners. OC, at the time the 4-4 plays were out of favor, not to make a comeback until late in the 19th century. Then White comes back to the push, 
in the game loses 21% to par, placing it in blunder territory, I think. Black should take advantage of White's error.
and 
, White will atari at a. This is a good result for Black. 
so maybe I'm misunderstanding something but... ) 