I regret building this $3000 Pi AI cluster

Guys, don’t take the claim so literally. He’s a successful tech poster. He makes good money showing off his purchases the good money complaining about how expensive they were.

But certainly don’t imitate his choices, his economics aren’t your economics!

Thats pretty much a given, but what the real takeaway should be from most of the content is that whatever you are doing, these days the answer in all likelihood is not to buy a raspberry pi. It's specs to price just do not add up at all anymore, and it's looking like a pretty damn stagnant place these days.

What if you need ARM? What is the best sub $100 sbc that I am missing? Orange Pi hardware always looks good but I hear a lot of negativity about the software that I don't really experience with Raspbian.

Then you should take a good hard look at older, much cheaper Raspberry Pis.

Then look at Apple’s ARM offerings, and AWS Graviton if you need ARM with raw power.

If you need embedded/GPIO you should consider an Arduino, or clone. If you need GPIOs and Internet connectivity, look at an ESP32. GPIOs, ARM and wired ethernet? Consdier the the STM32H.

Robotics/machine vision applications, needing IO and lots of compute power? Consider a regular PC with an embedded processor on serial or USB. Or nvidia jetson if you want to run CUDA stuff.

And take a good hard look at your assumptions, as mini PCs using the Intel N100 CPU are very competitive with modern Pis.

I've heard nothing but horror stories on the Jetson & Tegra in general. I'd Avoid it unless the project MUST use a SoM w/ CUDA. which will basically only be Professional stuff. I've never heard of anything hobby level where a PCIe slot was a deal breaker- even with high vibration. (PCIe 4.0 isn't terrible difficult to get good flex cables for)