For me, disc brakes vs rim brakes really isn’t about the weight or braking performance. It’s more about the fact that disc brakes open you up to much nicer tire and wheel options.
Those options were already available with cantilever brakes - I have an old dolan fitted with (TRP CX9) canti’s that can stop the bike no problem going down hill with a 45kg trailer behind it, in fact every bit as well as my Surly with GRX hydro discs. I guess that canti brakes are seen as old school and “touring” rather than cool and “gravel” though