I am big into wine, in particular old world but will enjoy and appreciate anything well made from $10 to $1000+/bottle. There are plenty of wines out there at the $15-35 price point that outclass many, many wines multiple times their price if you know what you are doing and what you are looking for. Perusing this list, the Duval-Leroy is a $60-100 vintage BdB brut, plenty okay but not what I would expect ininternational Flagship First. The other wines on the menu here are nothing special; the de Bortoli I cannot even identify based on the label. De Bortoli have more than one dessert wine and none of the labels look (or have looked) like that one that I can find (see: Our Wines | De Bortoli Wines). Vintages are not listed on this menu aside from the Champagne, and I presume all of the other wines are actually vintage selections (though of course they may not be) which is not very professional, either. The other wines are $15-35/bottle retail generally from what I can gather. That said, it is nigh impossible to find more than one of them available for retail purchase in the online marketplace and they must be exclusive partnerships with AA (probably plus a couple of other companies) to sell those specific cuvees on flights. Needless to say I would not expect them to be particularly high end.

I am wondering what the "somm select" wine referenced at the top of the wine menu actually is on a given flight.

I am going out on AA 20 DFW->LHR myself in early May in F. I wonder if this soft product "softening" discussed in this thread will continue further until AA phases out 3 class service in 2024. I certainly hope not but I am not optimistic. Thankfully my return trip I was able to book a codeshare flight on BA in first class on a 777-300 with the sliding privacy doors in F after a schedule change that AA dictated. From what I read BA puts a lot more pride in their F service.