I guess I'm confused that the projections in TFA are largely in line with the projections in the BBC article from 5 years ago. I'd expect something to have changed in that time (whether for better/worse), and it makes me suspicious that TFA is recycling 5 year old conclusions rather than presenting novel data

True.

I am usually buying the cheapest extra-virgin olive oil available (in Europe), and its price has increased by more than 50% in comparison with a couple of years ago.

If possible, try more expensive varieties as well. In some cases they're so strong you'll need less oil for a better result (or in my case, same amount of oil but for a heavenly experience). If you can find some online farmers, look for 5lt tins of oil, this way you'll save a bit. I just looked how much would be to buy oil in Tuscany where I live and get it shipped to France and it almost doubles the price, so I guess buying online from italy is a no no

You are right about the expensive varieties, which I buy sporadically, but I do not use olive oil for flavoring, but as actual food (it typically provides around two thirds of my daily intake of fat, or even more in the days with increased physical work that requires a higher energy intake).

So using a better olive oil would not make me reduce the amount that I eat, therefore I choose the cheapest EVOO most of the time (which is still quite good, even if with a less intense flavor; since I use great amounts in cooking, the flavor is strong enough anyway).

I didn't think about that. It makes sense, I was talking about flavoring specifically

Have no idea why you are getting downvoted. You definitely do need to pay more than average for a decent olive oil. And if you look, there are plenty of good options for high quality and high polyphenol oil at reasonable prices. Just have to dig. r/oliveoil is a good place to start as there are some good discussions and people like to post their finds. Be aware that there are lots of people in that subreddit that kinda sorta shill their own olive oil. Usually they are excellent oils but often quite expensive. Again, you get what you pay for for the most part.

Try Kali Agri. Extremely high polyphenols and all around excellent. Free shipping to US, but not sure about if that applies for the Europe store:

https://eu.kaliagri.it/collections/kali-eu

Olive leccino my beloved. It doesn't look too expensive, not cheap at all, but not so expensive

Yeah definitely not cheap like "this sucks" but extremely reasonable price for pretty high quality and high polyphenol olive oil imo. I like it a lot.