What? The chainsaw and berserker fists never locked me into a 2 second insta-kill attack animation when I played DOOM and DOOM 2.
No, you had to hold down the chainsaw on some enemies cause it took a bit to kill, while others were insta-kill. Faster more powerful enemies it was useless.
It was a good stress relief for marines and imps mainly, but then got old, and no one wanted to pick it up since you lost your fists.
Berserk was your gib insta-kill animation that was also rewarding like a BFG one hitter.
You are comparing limited tech with something that evolved. We all would have loved even a bit more than what was presented in the originals since I know like many others at the time, we daydreamed about those very mechanics evolving over time.
Can't wait to see complaints with an evoked chain gun cha cha.