That was a little after my time, but back in the 90s my second job after I got tired of being a dishwasher was at Radio Shack.
During the brief time I worked there if I sold a single Tandy Sensation! (had to say it with the exclamation mark) the profit on that sale would exceed, by a lot, every single component we sold the entire month, and as an awkward teen I sold a lot of Tandy Sensation!s per month.
At my store, when I worked there, electronics parts took up about a quarter of the square footage of the store but was practically none of our revenue.
The only people buying electronics parts were church AV guys trying to fix a worn out 1/4" jack or blown capacitor in an amplifier.
Can't pay rent on those guys.
As an outsider I watched the parts shelves go from most of the back of the store to a single set of drawers to nothing and I can't say I blame Radio Shack. A lot of time was spent inventorying a mindboggling array of components, none of which sold in volumes great enough to justify the expense or the space.