It's interesting that you mention apprentices to the great masters, which squares with my experience--- the most arrogant people, or at least the most abrasive and outgoing with their arrogance, are usually the 2nd and 3rd tiers, not the top tier. There are arrogant people at the top tier, but many fewer than I would've thought. I suspect it has something to do with no longer feeling a need to prove themselves, no longer feeling in competition with people, etc. There might also be a bit of branching out into other areas later in one's career that causes them to be a bit more humble, since famous people often try to become more generalist once they've gotten famous in a specific area, and it's harder to be arrogant in a very wide area than in a niche.
Among people I interact with, there seems to be sort of a peak of arrogance among people who are very good in a narrow area in their 20s and 30s, while famous people in their 40s or 50s are often quite humble and generous in their evaluation of other people. At CS conferences, for example, you don't find folks like Donald Knuth asking pedantic dick questions very often, but you do find the "ugh how could anybody not have read [x], did you even do any research?" type attitudes from junior profs and grad students.
Among people I interact with, there seems to be sort of a peak of arrogance among people who are very good in a narrow area in their 20s and 30s, while famous people in their 40s or 50s are often quite humble and generous in their evaluation of other people. At CS conferences, for example, you don't find folks like Donald Knuth asking pedantic dick questions very often, but you do find the "ugh how could anybody not have read [x], did you even do any research?" type attitudes from junior profs and grad students.