The median (#50) senator under this ranking was Murkowski. 2022 seems to have been an exodus of moderate Republicans, as Portman, Shelby, Blunt, Burr and Toomey were all rated among the body's most moderate senators.
Then those ratings may be balderdash. Shelby and definitely Blunt were by no means moderates, and even among the Senate GOP caucus I doubt Shelby (and definitely not Blunt) would have made it into the top ten most moderate.
Senators like Blunt and Shelby sponsored/co-sponsored way more bipartisan legislation that most of their senate collegaues, either Republican or Democrat. That they don't give moderate ~vibes~ is immaterial.
They were both very good senators in that they were mostly working behind the scenes to champion issues critical to their states, while generally avoiding making a splashy cable news issues that only engage partisans.
They may have been very establishmentarian, but they were definitely not "moderates." The two are not the same.
I'm sure you'll agree that someone like Lisa Murkowski and someone like Roy Blunt, even if the latter is somehow defined as a moderate, are fundamentally two very different kinds of "moderates."
My definition of the term isn't broad enough to encompass somebody like Blunt, who was a typical Republican who almost always voted the party line on any controversial issue. Your definition of moderate is apparently anyone who doesn't seek the limelight and cosponsors enough bipartisan legislation. That's simply a regular establishment Republican, and in the Senate, it's still the majority of GOP senators (the House, needless to say, is another story).
Keep in mind that when you talk about bipartisan legislation, that is (in most cases) the very routine, nonpolitical legislation that most senators ultimately vote for except the biggest show horses and grandstanders - cosponsoring that, to me, means diddly squat in terms of providing moderate bona fides.
