Liberal reformers have been trying to change the dysfunctional Senate, and today they announced a compromise plan that will introduce very tiny alterations.
Decades ago, if you wanted to pass something through the Senate, you needed 51 votes, unless some Senators were really, truly upset about it (usually, if they were Southerners and the bill involved civil rights). Gradually, the rules changed, and practices changed, so the very unusual filibuster evolved into a routine supermajority requirement that is not in the Constitution even though everybody thinks it is.
The reformers didn't propose anything as crazy as changing the rules so that whichever side has more votes wins, because that would be communism. Instead they proposed compromise reforms to force people holding filibusters to actually hold the floor and talk. The trouble is that Republicans opposed even that. So the only way to pass any changes was to exploit one of the myriad bizarre Senate rules that allows the majority to change the rules any way it wants, but only on the first day of a session, except that the first day somehow lasts three weeks. (I am not making this up.)
But several of the older Democrats didn't want to do that. The Senate is a club, and its impenetrable rules and customs are bound up with the boundless ego-stroking its members are lavished with, and lavish each other with. The essential Senatorial belief is that to be a United States Senator is to establish a bond of prestige with one's fellow Senators that is stronger than party, ideology, or any rational sense of good governance. That sense has weakened in recent years, but remains strong with the back-slapping old-timers like Carl Levin, who helped sink any reform.
The compromise tinkers slightly around the edges. There won't even be a talking filibuster. Instead, there will be some procedural changes, the gist of which will be to make it harder for the minority to tie the Senate up in knots. As it currently stands, the minority side can stop all business for days on end pretty much at will, and that's what this compromise will limit.
Basically, what happened here is that the good government instinct met the senatorial ego, and the latter prevailed because it is the most powerful force on Earth.