ok to understand the appeal of the loaches* we have to go back to Vietnam with the oh-6 cayuse.
most of its down sides where intentional the cayuse was designed as a observation and scout chopper that's why they look the way they do the canopy style and slim profile allows for a better fov than other helicopters (without taking your hands off the stick and collective you can slightly lean out, look over your shoulder and see the entire rear profile of your heli I dare you to do that in an mi8). the oh6 was also quieter and still is than most helicopters and due to its slim profile its more nimble and able to fly and land in tight spaces if I needed to get down on the deck and do gun runs you could and more importantly harder to hit and cheaper to produce. the oh6 also earned a reputation for being extremely rugged and in almost every case if it crashed you could walk away from it. the appeal today lies in its maneuverability and its potential to excel in urban ops and at rapid insertion for example with a transport helicopter to insert in to a city or on a rooftop you have to approach high and slowly descend (its harder to slow a large object than a smaller one), find a large open field, or hover and repel add that to the fact that your in a large helicopter and now your a big slow juicy easy to hit target where as if I was in a loach I could come in low ( depending on obstacles present) and quickly transition from flight to landing and land on a rooftop shielded from fire or half land on the roof or if I needed to land in a 2 lane road then quickly accelerate and gtfo. in short the killer eggs are meant for close in dirty work, rapid tactical insertions in difficult terrain, observation, and are used more for quick precise sec ops missions where something like the chinook or mi8 is meant more for getting boots on the ground.
I mean if the little bird was a pickup truck a Blackhawk would be a box truck and a chinook/ mi8 would be a semi... hell if you took the skids off the little bird it would be just a little bigger than a pickup
in the end the mi8 is made for a completely different role than the little bird
the mi8 is more comparable to the chinook the hind to the Blackhawk and the mh-6/ah6/eh-6 to the ka-226
* loach is a nickname that stands for Light Observation /Attack CHopper the original official desiglation letters where LOH or light observation helicopter
I'm going to put a link down here I did in no way check its sorces and it may not be 100% accurate but its a good start into understanding the loach series you can also watch docs on it on youtube
https://www.militaryfactory.com/aircraft/detail.asp?aircraft_id=830