Perhaps because Democrats control half of Congress today, and the general trend of Congressional avoidance-of-clear-rulemaking has been the same even during those periods that Dems or Republicans control both chambers.
And: if Senate majorities really want to pass something, they can change the filibuster rules – and have, for some topics.
Otherwise, the filibuster is maintained out of tradition, courtesy, and its usefulness as a change-of-control 'debounce' mechanism – as well as providing a convenient excuse for posturing more and doing less, as Congress is wont.
Still, in other eras, Congress was able to move compromise legislation forward. Recently, Congress has been unable to – both parties, no matter the relative control. Any belief that it's only "the other guys" is partisan myside blindness.