Then again not like the "very shoot ourselves in the foot, but just little bit, instead of lot" on decades long repeat leads to anything good.
If ones vote is to be taken for granted, you have no power. Only way you can hold your own side accountable is by threatening to withhold the vote.
That is bargaining. Voting Democrat nomatter what and after that asking could they please do something, that is begging. Begging rarely works as well as bargaining.
Damned if you do, damned if you don't. Joys of two party system.
Most likely people just get apathy and instead of flipping to Trump, they simply stay home. Which is the other bargain. What you offer for me to bother to go from my home to the voting station in the first place.
That is their play "you can't take us for granted anymore, we care about our vote and bargaining power on long term enough to suffer on short term to buy long term relevance".
Whether it works is different matter. I don't know, if democratic leadership has the where with all to take their left flank of voters as anything but given serval supporters to be kept in line with "but we are only little bit bad, those guys are really really bad".