Enemies in games that are much harder than bosses?

I beat Ninja Gaiden Black 2 and something I notice is I had very little trouble beating the bosses compared to the enemies. Not sure bosses were nerfed in Black because I struggled with them back in the OG 2. Here, piece of cake. My total losses from the boss fights were about 5 while my total losses against common enemies were more than that. Like holy hell, I just kept getting jumped by most enemies and trapped me into a corner. Like give me a break. Even got killed by the dogs. Those mutant cyborgs were the worst ones.