Strange, any phone today would be better than most hardware we had 30 yrs ago. In the 90's I had monitors with resolutions of 320x240, limited info on the screen. Things were slow. If you gave me the option of using a phone from today or a computer from then, back then and today, I'll definitely pick the phone. We don't code at the speed of thought, we poke at the computer one key at a time, one register at a time.
Not about the speed, it's about the comfort for me. And 30 years ago would be the mid 90s so most people had 14 inch monitors that supported 640x480 or even SVGA at 800 x 600 with ease.
To me, it doesn't matter how many pixels your phone is displaying when you're limited to a whopping 6 inch diagonal.
And I can't even imagine torturously attempting to touch type on the phones keyboard (which is displacing even more of your limited phone screen), versus a dedicated mechanical keyboard which was also common at the time.
I wrote code with a cheap logitech keyboard and a phone. The keyboard keeps phone upright. The screen is enough for text. But touchscreen for typing? nope thanks give me a 30 yr old computer