Fresh cheese, such as mozzarella and ricotta, is quicker to make, and a lot less concentrated. It doesn’t need ageing, and there’s a lot less milk going into a kilo of cheese. It’s also less work.
On the flip side, they don’t last as long. If you want to get fresh ricotta and you live far away from where it’s produced it might cost you a fortune, as it cannot be stored in the cheese shop as long as a wheel of aged cheese.
Good cheddar is expensive. I suspect this graph is very generous in what it considers cheddar.
It:'s also fundamentally a bit weird to compare the prices of these cheeses, as cheese prices tend to be extremely local in nature. What’s a fancy foreign cheese in one place is just traditional food in another. And of course, price and quality varies a lot within each cheese. A lot of what is sold as mozzarella is also not recognizable as such in my opinion.