The mid 70's were a time when a teen with a dream and some side job/hustle could walk into one of the ubiquitous stereo stores that were around and say- one day. And the dudes who worked in the stores, often half stoned, didn't mind the company
your first system-
I put together my first system in 1977- turntable, receiver, speakers and a cassette deck- $600. An on-line inflation calculator tells me that is $2760 in 2022 dollars. I am sure a current $1500 streaming based system can be assembled that would demolish my 1977 system. That's what I call real progress!