> Radio Shack gutted itself, IMO, albeit probably in response to the reality that they couldn't sell very many single 555 timers for $1.99 anymore once people had obvious alternatives.

I don't have any firm numbers on this, but I doubt that discrete components for building circuits from scratch were ever a significant portion of Radio Shack's business. Seems like most of their sales were in manufactured devices (for example, amps, pocket radios, walkie talkies, computers), accessories (antennas, microphones), cables, replacement tubes for radios and TVs, and, of course, batteries.