For example: Wine tasters were clear that French wine just tasted better than Californian wine. They were extremely convinced. Then they tried a blind test and hoo boy did everyone get pissed when they couldn’t tell the French wine was better without knowing it was French first. https://en.wikipedia.org/wiki/Judgment_of_Paris_(wine)

Two Buck Chuck (an inexpensive blend of wines sold by Trader Joe's) also has scored well among California wines. So it's not like expensive California wines are obliterating more-pedestrian counterparts, either.

https://en.wikipedia.org/wiki/Charles_Shaw_wine

Charles Shaw is an American brand of bargain-priced wine.[1] Largely made from California grapes, Charles Shaw wines include Cabernet Sauvignon, White Zinfandel, Merlot, Chardonnay, Sauvignon Blanc, Shiraz, Valdiguié in the style of Beaujolais nouveau, and limited quantities of Pinot Grigio.

The cost of the wine is about 30 to 40 percent of the price, with the bottle, cork and distribution the larger part.

Charles Shaw wines were introduced at Trader Joe's grocery stores in California in 2002 at a price of USD$1.99 per bottle, earning the wines the nickname "Two Buck Chuck", and eventually sold 800 million bottles between 2002 and 2013.[2]

At the 28th Annual International Eastern Wine Competition, Shaw's 2002 Shiraz received the double gold medal, beating approximately 2,300 other wines in the competition.[13]

I'd add that the same sort of thing goes for "audiophile" gear. Things should be blind-tested. It's very easy to have a perceptually different experience when you know what it is that you're using.

I remember a point where Joshua Bell was busking in the New York subway.

https://www.classicfm.com/artists/joshua-bell/violin-busking-washington-subway/

He’s one of the finest talents in the classical music world, and in 2007 violinist Joshua Bell went busking as an experiment. Would the public realise just what was happening, alongside their daily bustle?

Music director of the Academy of St Martin in the Fields, worldwide star soloist, and former child prodigy. His instrument is a Stradivarius from 1713 and his hair is an icon of classical music in itself....

Joshua Bell is one of the world’s great virtuosos, and one of the biggest names in classical music.

And in 2007 he did some anonymous busking, as a little social experiment to see what might happen.

Over a period of 43 minutes, the violinist performed six classical pieces, two from Bach pieces, one Massenet, and one each from Schubert and Ponce.

Out of 1,097 people that passed by Bell, 27 gave money, and only seven actually stopped and listened for any length of time.

In total, Bell made $52.17 (£42.18). And this includes a $20 note from someone who recognised him.