Stop in for a cup of coffee
I'll disagree with you guys on that.
The mistake was on some models labelling the ammeter "Alternator"
That confuses a lot of people.
The ammeter doesn't provide any info about the Alternator - Sure had me confused for years. Rather it shows the current to or from the battery.
Having a better connection through firewall from the alternator to the main splice was done on some models and years. From an assembly and service point of view, using a connector at the firewall makes sense. A heavier gage or better connector, yea. OK. I agree that would be better. And they did that for some fleet vehicles. But it would have been overkill for most.
One clever part about the design is it means only one fusible link is needed. This means the power goes from the alternator to everything without any drops in wire size of the main trunk.
Where the design begins to be an issue is when the electric system has to power equipment that draws more than the alternator can handle. It also fails when accessories are added to battery instead of the alternator - but that's not a fault of the design.