I would interpret "classic" as chips which made a huge impact. If they did that they are probably still used occasionally just because of inertia, the mass of existing documentation and enormous piles of NOS parts still flooding the market. There are few, if any, 40+ year old chip designs that are currently the best choice for new designs, though there are several that are adequate in many applications.
Two I would add to the list are the CD4046 PLL chip and maybe the CD4060 14 stage ripple counter w oscillator.