Depends upon how you define Personal Computer and what time-frame you look at.
So if you define a personal computer as a computer people use for personal tasks as a tool, then a mobile phone fits that. In that definition and if you look at all the years history wise, It does look like Nokia have sold the most computers for personal use. At least going by the numbers sold per manufacturer https://en.wikipedia.org/wiki/List_of_best-selling_mobile_ph... and mobiles selling way more than other forms of computers.
Smart phones are not personal computers and the kind of dumb phones around in that year weren’t even smart enough to be computing devices. My phone back then was “amazing” because it had an inbuilt FM tuner AND supported custom ring tones (think PC speaker quality rather than MP3s). I think I could store a maximum of 50 text messages too and that felt like a lot.
It’s sometimes hard to believe how young smart phones (and in fact portable mobile phones in general) are by just how much we now depend on them and take them for granted.
the big three have been Lenovo, HP and Dell for a long time, order of those has switched sometimes. so depending how you slice the share, you could find a niche where somehow it would appear as whatever you want it to be, usual thing when reporting market shares: "we are top in this is super-niche slice of the overall market"
So if you define a personal computer as a computer people use for personal tasks as a tool, then a mobile phone fits that. In that definition and if you look at all the years history wise, It does look like Nokia have sold the most computers for personal use. At least going by the numbers sold per manufacturer https://en.wikipedia.org/wiki/List_of_best-selling_mobile_ph... and mobiles selling way more than other forms of computers.