Looking at a list of dams removed in the US, it seems to me that most of them were not hydroelectric dams, and that most dams were removed because they were old and not economic and/or not safe. Then again, while many were old, small, inefficient and obsolete, it doesn’t help that sediment fills up behind the dams reducing their benefit and eventually causing a safety issue.
There appears to be no intent by the US to move away from hydropower.http://energy.gov/eere/water/downloads/hydropower-memorandum-understanding
“The MOU established 13 overarching goals for sustainable hydropower generation and identified a specific set of activities that the Agencies collectively would undertake to elevate the goal of increased hydropower generation. These commitments were designed to represent a new approach to hydropower development that would result in clean, renewable power generation while avoiding or reducing environmental impacts.”