the idea simply was that by charging it at cost, it makes it affordable as it can be across the world which is an admirable sentiment. Pfizer and Moderna went for the bucks from the start.
The other aspect about AZ is that it doesnt need specialist freezers to keep it viable. Remote locations around the world just dont have the correct equipment
In fairness the russian vaccine can be shipped in solid format and is also cheap and equally effective so they have actually done the world a favour too although not much is heard about that