There's an additional problem with Brink Lindsey's argument.
Democrats were able to make gains with libertarian voters without
doing anything to specifically court them, so there isn't much
incentive for Democrats to suddenly risk alienating their base to
pursue polices being pushed by Lindsey, such as "restructuring" of
entitlement programs, just to win over more libertarian votes. From
the Democrats point of view, a growing number of libertarians will
be inclined to vote for them on the basis of national security and
social issues anyway, so there's no need to seek reconciliation
with libertarians on economic issues.