I’ve never thought of it that way. Come to think of it, I could name many of the influential people at Apple from the 1970s through the 1990s beyond the founders and CEOs. Bill Atkinson, Larry Tesler, Ike Nassi, Alan Kay, Susan Kare, Chris Espinosa, Johanna Hoffman, Jean Louis Gassée, Steve Sakoman, Bruce Tognazzini, and Don Norman immediately come to mind. I can also name many of the key NeXT players, like Avie Tevanian and Bertrand Sertlet. However, with the exceptions of Jony Ive and Scott Forstall, I don’t know the names of key engineers and product designers at Apple these days. This may be due to Apple’s evolving culture of secrecy.
Outside of WWDC (which isn't even in person anymore) Apple doesn't seem to allow its technical staff to have much public visibility. On the other hand, the decline in visibility you cite might also correspond somewhat with a media shift toward the web and social media. I expect Apple has strict requirements regarding employee blogs and social media presence.
It's a shame, because Apple has great technical and design staff, and it would be nice to hear more from them.
But of course Apple is also a much larger company now than it was in the 1980s-2000s.
