That was true then, but we have more aggressive and capable sharpeners today.
Another factor was geometry: Because stainless wore out factory abrasives faster (a significant cost difference), stainless knives were often not ground as thin, even when of the same model as a Carbon version (this probably did not apply to Randalls). I have seen 3 Sabatier Jeune knives from the 1940s and 50s, two stainless and one Carbon, all identical looking models (a sort of French Kabar), and the two stainless versions were ground much thicker and duller than the supposedly identical Carbon example: There was no comparison in finesse or ease of sharpening. Once fully re-ground to 0.010", the stainless knife became somewhat comparable: Still harder to sharpen, but a comparable and longer lasting edge.
Even today, most stainless outdoor fixed knives, outside of Randalls, are ground to 0.040" at the edge shoulders (or even thicker as a convex equivalent, such as the San Mai Trailmaster): This is absurdly thick. Randalls are barely half that, hollow ground, and yet hold up quite well.
In those days, there were fewer quality stone sets that could do a heavy reprofiling/thinning job: There was a lot of junk hones that could not handle anything difficult. Thicker stainless edges, and the usual worn out single grit hones meant the typical stainless outdoor knife had the thick rounded edge of a butter knife.
Faced with using simple stones of uncertain grit and surface stability (as I used until the mid 90s: Even from the same brand, coarse stones varied greatly in how they would keep their shape when sharpening: Stainless would routinely create uneven "grooves" in them, or simply "dip" them into an uneven curved shape), I also would have preferred Carbon steel in the 1980s and even the 90s: No big Carbon steel factory knives were offered. Today diamond hones mean Carbon is no longer necessary, yet now almost all the big factory knives are Carbon...
Gaston