I'll have to be a fence-straddler here. Oftentimes there's no substitute for
more I/O pins in terms of hardware complexity, and often the larger chips
are the only ones that offer the other peripherals I need. OTOH, I'm
frequently doing stuff with remote displays, etc, where I want to minimize
the number of wires running from one board to another. In this case, shift
registers are invaluable. For instance, right the moment, I'm running an
LCD, several LEDs, and several buttons at the end of ~4 feet of ribbon
cable, using only 8 conductors. If I dedicated a wire to each I/O, I would
end up with ~20 wires... yuk!
As with most things in EE, it looks like the answer to this question depends
on your individual problems and design goals.

- Robert

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