In fact, this is a hot resarch agenda that test macro theories with heterogeneity amoung countries and different groups of firms.
But generally speaking, economics theories are robust and able to explain all kinds of scenario, given proper assumptions.
Asymmetric information is important even in U.S, when you look at more empirical test you will see there is a large number of papers have confirm that perfect and complete capital market assumptions doesn't stand. you can refereed to Fazzari, Hubbard and Peterson (1988), Bond etc (1998) to see evidence for asymmetric information for mature capital market in the european countries and U.S