How much a mic picks up an untreated room?

if you don’t wanna go the sleeping bag route then, yup, make some 6 foot high frames and a ceiling for them and fill them with 4" rockwool slabs. cover with mice cloth. You vocals will suddenly be devoid of that horrible smear all those hideous reflections cause and will be MUCH EASIER to mix as they’ll be a squllion % clearer