@rhys I'd say the problem is that Democrats proved themselves uninterested in substantially fighting for their positions, so electing them just indulges the exact failures that lost them the election.
The only way to have them improve is to refuse votes until they get better.
For example, Democrats could take over the House. Republicans are so splintered with a small margin that Democrats could take the majority and really start countering Trump. But they're not interested in that.
Until Democrats actually decide to put up an opposition, why should we reward them for political posturing?