1: its a half fangame
2: do you seriously think the NES would handle the amount of sprites (like shockwaves from bombs, fire orbs and the various ERAM clones with literal FIRE TRAILS)? for fuck sake the CPU clock speed of the NES is 1.79 MHz... for comparison we have long surpassed 1 GHz as our base clock speed
TLDR;stop thinking developers can be fucking wizards and shut your trap