[Migraine]

The check on the filibuster is 1) make them actually speak the full time, and 2) keep the Senate in session until judicial nominations are voted up or down. Why is that so hard?
The Vatican has that feature when selecting a new pope. The word, "conclave", which the session is called, literally means, "with key". The cardinals are locked in a room until they have a decision. This policy resulted from an era in which it took, sometimes, 3 or 4 years to get a new pope. Obviously, the office was too important to go vacant for such lengthy stretches.
Ditto judgeships.

[rellimpank]

--it is difficult because of the collective spinelessness of a majority of the "majority" party, compounded by difficulties with their left wing from the Northeastern states--

[bluecollarman]

"Why is that so hard?"

It is not hard...they just don't want to. They will send young men to die for this country but they can't be inconvienenced. No, they won't disrupt their schedules by fighting for their convictions, that's just to hard on them.

[MrLeRoy]

The check on the filibuster is 1) make them actually speak the full time

Precisely---and as I understand it, that is within the Senate GOP's power.