About to leave for Greece.
Was going to get the Orange Euro eSIM but they currently say the 100 GB bundle is unavailable. Never seen that before.
I may try the Cosmote. Can't really tell from their website because it's only partly in English but they offer eSIM, though it's not clear they offer prepaid eSIMs. Also not clear if I should spend limited time going to one of their stores.
Here's an option I just found, Vodafone seems to be selling eSIMs directly online.
https://travel.vodafone.com/our-destinations/europe
Price isn't as good as the Orange eSIM and you figure you don't roam on as many different networks. Vodafone may have good networks in some countries but not clear it's good in all the countries.