These, the convention wisdom would go, are the experienced members, measured in their actions and taking seriously their position in this most august body. Senate Minority Leader Mitch McConnell tried to reinforce this idea by talking about the reformers—Sens. Jeff Merkley and Tom Udall—as a "cohort of short-sighted Senate sophomores." Young barbarians at the gates!
That would be a convenient argument against changing the rules, if it were wholly true. There are actually some long-serving current and retired senators who think a rule change is absolutely in order, as Jonathan Backer from the Brennan Center for Justice, writes.
Senator Tom Harkin, first elected in 1984, has crusaded against the filibuster for years. Unlike his more junior allies, who wish to preserve the filibuster while limiting its abuse, Harkin’s preferred course is to ensure that all legislation eventually receives an up-or-down vote. In 1995, when Republicans controlled 52 seats, Harkin, a Democrat, first offered a resolution that would gradually reduce the number of votes required for cloture — the mechanism to end a filibuster — to 50 votes. [...] Senator Barbara Mikulski, the longest-serving woman in Senate history (first elected in 1986), has repeatedly co-sponsored Harkin’s proposal.These long-time members and former members of the Senate are no less serious about their commitment to public service than any reform opponent. They have no less reverence for the Senate as an institution than their colleagues. You could easily make the argument that they take these things far more seriously than the whole of the Republican senate caucus which has used the current rules to blow the place to smithereens.
Senator Frank Lautenberg, who has served since 1982 with a brief two year hiatus, is also a major proponent of filibuster reform. Like Merkley, Lautenberg believes that filibustering senators should hold the floor and actually debate so that the public can see who is preventing a vote. [...]
And respected former Senators Jack Danforth, a Republican, and Dan Boren, a Democrat, both recognize that the modern filibuster is not in line with the Senate’s tradition as a deliberative body.
The filibuster reformers are the real protectors of the legacy of the institution. It's supposed to be a functioning arm of government, the "cooling saucer" of legislation. Instead, Republicans have made it the deep freeze.