My first PIC was 16F84. Choice was easy. Not only that Microchip had relatively few models those days but almost all were of higher price. Yes, brave men would go for write-once chips, but that was pain for any kind of learning or development.
I considered this chip as pure jelly-bean part. I would always have few around. Whatever I designed it was around it (with some exceptions, of course). I probably ended-up using it in 90% of my projects. And I would never run out of it. If there wasn’t any in new parts bin, I would just pull one from old project. Good old days of DIP.
As time went by, there came much more powerful chips but I liked my old trusty 16F84. It took huge price increase from Microchip for me to look for replacement.
It was only natural to select 16F628. It was better chip (good bye USART bit-banging), it was cheaper and it was almost completely pin-compatible with 16F84. These days this is considered quite a modest chip. There is no ADC, no PWM, no I2C and price is rather high for what you actually get. Using it in new projects was just not a real option.
Since last year my default choice fell on 16F1826. It is decent device and it has all things that modern PIC should have. And it is cheap and stocked almost anywhere.
But when I contrast it with good old 16F84, I notice that I am nowhere near 90% usage. Somehow my projects always end-up using more pins that this little gem has or I need some more advanced functionality (e.g. LCD). I probably spend hours looking for micro-controller and then cross-referencing this data with stock in RS or DigiKey. And that is time I lose each time I start something new.
Not even jelly-bean components are what they used to be.
P.S. Yes, I am old and looking back toward good-old-days.