Let me start by saying that in principle, the filibuster in the Senate - used judiciously and sparingly - was a good thing. There are times that the majority needs to be slowed down, that a certain nominee should not be approved despite having majority support, or legislation needs to be blocked. But for it to work, it needs to be used sparingly, rarely, and in only special circumstances. And until Barack Obama became president, this is how it worked. Senators had an understanding in this regard, that even if they could use the filibuster, they shouldn’t use it unless it was, as was agreed upon in 2005, "extraordinary circumstances". At that time, Republicans were threatening to change the rules, and that was just offer a handful of federal judges. The Democrats essentially capitulated except for a few judges. A deal was struck, and the rules remained intact.
Now Democrats are being accused of hypocrisy for changing the rules now when they criticized that idea eight years ago. And on the surface, it would seem to be hypocritical. It is not. It would be hypocritical if they did this under the same circumstances, for a only a few judges, but that is not the case. The Republicans have made the use of the filibuster routine for scores of President Obama’s appointments, to either kill or delay them - sometimes for years. They wanted to cripple the government since they couldn’t take it over at the ballot box. And it is clear that the Republicans reneged on numerous promises to stop using this tactic.
The democrats in the Senate were not hypocrites to change the Senate rules when one looks at the numbers.
One must honestly compare the situation in 2005 and the agreement made then, and also the historical understanding about the limited use of the filibuster, and realize that a change had to take place. The Republicans abused their power in a way that was unprecedented. The Democrats are not hypocrites for taking action. The circumstances had dramatically changed, for the worse.