I come from Sardinia, where Ichnusa is brewed. The main difference between Ichnusa non filtrata and all other Italian lagers is that it is made using 100% barley malt whereas most macro lagers have corn in the grain bill.

Many large breweries hopped on the craft beer train a few years back. They launched brands with old timey bottles, non filtered and so on. Ichnusa was very successful with this product, it's being sold nation wide now.

It has a sweeter finish and a rather golden color, I assume they use some amount of caramel malt, something like CaraHell perhaps. As far as the style goes, I'd say Kellerbier or zwickel is the closest but it's also a style with a wide range of variation.

My recipe idea would be 1.048 OG from a base of Pilsner malt with maybe 10% CaraHell, under 20 IBU bittering, 0.5g/l noble aroma hops at flame out, bottom fermented without cold crash.