Democrats fail to act in unison when they are in power, unlike the Republicans who are much more disciplined in this regard. They also realise that much of America is conservative at its core and will not tolerate views or actions that are too far left of center. For far too long, they have relied on the Courts as a way to do an end-run around legislatures, where they are ineffectual at getting their agenda passed. Now that has come back to bite them in the ass. The Republicans have put conservatives in many important courts now, blocking this (undemocratic) avenue for pushing forward Democrats' agenda. The Democrats would have been better off pushing for a Constitutional Amendment in the first place, but in 50+ years, they have do zilch towards that, giving the lie to their claim that they are pro-women or pro-choice. They are pro-power, as are Republicans, and that's the end of the story. Now they are forced to do the actual hard work of passing legislation or amending the constitution, for which they do not have a mandate from the public.
Of course, the Democrats have already started making noises about following another unwise course, that of packing the Supreme Court by adding more justices that they can install. They will find in due course that they will fail miserably there as well and face a profound backlash.