I suspect (and this is just speculation) the M1 is very closely related to their iPad architecture which was never designed for more than one external display, as such the architecture wasn't really suitable and between building a 'computer' based on that chip and re-architecting the design it just wasn't feasible or required to support it on the first release.

Thats exactly my thought too. Makes me wonder if it will support two monitors in clamshell mode since the mac mini supports two. I guess we'll have to wait and see. Maybe it's something they can patch in.

I'm also curious as to how the graphics connections / routing works; would they have an internal bus and then split and mux it or something? Or perhaps an eDP or LVDS bus that can't be switched out to some HDMI or DP transceiver in clamshell?

Let's see if iFixit can get us some nice high-res pictures. Heck, someone might leak schematics and any normal users can probably show a IOTree for the system. Always nice to explore those on new machines.

Very much agree, I wonder as well. In other news, are there any adaptors out there that let me plug in two 4K displays and pretend to be a double wide single 4K display?

Yes, I think Matrox is one of those that makes them.

It’s the first release of a new product? Features take time.

I mean, all they're asking (and me too) is feature parity with what existed on the line before.

If they can't deliver that, it probably should have been held back.

That's a pretty damn important feature, especially for professional users.

Agreed. If you think about what’s common between all the types of “professionals” that Apple targets, from coding to music production to whatever... one of them is wanting multiple screens to have everything laid out in front of them.

That’s not really the market for these models. The Air and the low end MacBook Pro only have two ports and are not really well suited to working with multiple external monitors. I suspect that, when Apple update the higher end machines, that they will be able to support multiple external monitors (and more RAM). The M1 is more of an MVP at this point.

Can’t the RPi 4 support dual 4K?

Technically the M1 can support 2 displays too, 1 @ 6k/60Hz and 1 @ 4k/60Hz. This is done eg. for the Mac mini. However, for the laptops, one of those is consumed by the built in screen.

Which is weird because every laptop I've had for 15 years has had a mux on the RAMDAC outputs so you could connect as many external screens as you can have max outputs and just turn off the builtin screen.

Including Macs.

dual 4k or dual monitor?