What is something that's crazier than the wildest dreams of any ~1970s nerd, but exists today? I'll start with an easy one:

That image has gotta be fake, right?

SDHC only goes up to 32GB and I’m pretty sure the successor SDXC only goes up to 2TB

I’m not quite sure how a card can be both U1 and U3 too

SD express should be able to surpass 2TB, but I don’t know if 4TB micro SD express cards have been made yet

You are 100% correct, there is no such thing as a 4TB SD card. Largest you can get is 2TB. Western Digital has shown a 4TB MicroSDUC and even 8TB SDUC card at shows and events, but I don’t think it has found its way into production just yet. And with the extreme prices of flash these days, I doubt they will release it any time soon. The 4TB card would probably be $1500 - $2000 retail, who is going to buy that? And what is the use case?

The picture is some mockup someone made or maybe AI generated, but not of a real card.

It could be a real card from Temu. It’s actually a 1 GB card, but it says it’s 4TB.

You can actually store 4TB on most those cards (if you’re ok with automated data deletion to make room)