I'm pretty sure no NATO countries actually consider the US a dependable ally at the moment. So US spending is kind of irrelevant really. And if the US were to actively work against its NATO allies (seems pretty likely at this point), US NATO spending would be considered more of a negative rather than a positive.
As a layman, I think this opinion is wrong. I think it's clear that the EU position vis-a-vis Russia would have been greatly compromised had it not been for the magnitude of U.S. military spending.