Ok let's break it down, only 1 of your examples is pre93 most are 10 years after that cause mixtape weren't around like that in 93 and everybody wasn't rapping on each other beats like that.(jackin for beats being the exception, the reason that was a big deal is cause people didn't rap over each others beat back then)
Tupac dissing biggie in 95 overall biggie beat?, I don't remember that but it's not 93 anyway
And as for Antoinette lyte, antoinette rapped over a beat similar top billing CAUSING lyte to diss her, know why she dissed her?, cause people didn't rap over other people's beats back then.