Earlier quoted context omitted.
No it's not? A typical bottle should be about 5 glasses + or - one depending on how you pour.
This. I pour 5-6 glasses of wine from a bottle, and I don't feel that they're "small" in any way. Putting a third of a bottle at once in the glass is far too much - at that quantity, swirling the wine becomes nearly impossible. And anyway, holding a wine glass should be effortless, you should be able to talk & do mild gestures with the glass in your hand.
https://www.askitalian.co.uk/menu/menu/drinks/
https://www.jamieoliver.com/italian/restaurants/birmingham/m...
https://www.nandos.co.uk/food/menu
https://www.zizzi.co.uk/drinks#white
etc etc.
And these large glasses are used in many homes. I have no problem believing that people are drinking glasses of wine this big, mostly because I see them do it.