no, you are saying the alt is fused ( by itself ) which is not, not even the ign system by itself but just by the fuse link on batt line which protects ALL the car, not the alt or the ign system itself LOL, like the dedicated fuses on the fuse box. The fuse link is protecting all the car from the BATT power. Just like the Racing cut off power switches do in emergency case ( adding the ign circuit cut off feature to save from the alt/reg feedback if it happens ).
we are not talking about last 25-30 years but the cars on this discussion LOL