"For that price, you can just use an old laptop" has been true ever since the OG Raspberry Pi showed up ~13 years ago.
And that's great, and stuff, if what a person wants is the most compute they can get for the fewest dollars possible.
But when someone instead wants a quite small computer that is actually friendly to hardware tinkering, and they want to buy it new, then a used Thinkpad will not scratch that itch -- but a new Raspberry Pi will.
(It's a bad comparison. It always has been a bad comparison.)
13 years ago, we only had the Raspberry Pi Model B at $35 (about $50 in today's money -- same as a 2GB Pi 5), and just as today we still needed to get all of the accoutrements in-place to make it work: A power supply that it actually works with, a case, an SD card, perhaps a wifi adapter...
$150 is plenty to buy a used PC system here in 2025 that still works, just as $100 was plenty to buy a working used system in 2012.
As a point of reference: The last used system I bought was a little Lenovo M600. It was $50, delivered, a couple of years ago.
As another point of reference: My daily-driver laptop is a Thinkpad T530 that was ~$200 (I paid a little extra for a disturbingly-clean example that included a discrete GPU and the fanciest of the screens that could be equipped).
Anyway: I saw these same discussions about pricing back when the first Pi was still new -- just on Slashdot instead of HN. People have been comparing the prices of used PC hardware to the prices of new Raspberry Pis for as long as we've had Raspberry Pis.
(And to be clear, I'm not trying to fanboy anything. This isn't Highlander: There can be more than one. I've got Raspberry Pis that do stuff, and I also have PC hardware that does stuff, and I'm OK with this.)
And that's great, and stuff, if what a person wants is the most compute they can get for the fewest dollars possible.
But when someone instead wants a quite small computer that is actually friendly to hardware tinkering, and they want to buy it new, then a used Thinkpad will not scratch that itch -- but a new Raspberry Pi will.
(It's a bad comparison. It always has been a bad comparison.)