I’ve seen dude on the PCT walking in sandals and a jansport backpack. I’m sure it COULD be done.
I however don’t often do UL. It’s either expensive or super minimalistic. I can afford the expensive part, but I like the durability of the gear I use, even if it weights a few more ounces. I’m not sleeping in an open tarp, too many frogs, snakes, bugs, rodents etc running about. Wind driven rain is a concern too. The whole point is to get good sleep so I can’t put in miles the next morning.
That said a tent takes up have the space if a 3600ish size. There’s a sacrifice in everything, but you might make it work if you attach the tent to the outside of the pack.
Idk about fitting 5 days of food, some layers, a sleeping bag, sleeping pad etc plus hunting gear though…that sleeping bag needs to roll up pretty tight…