Bought a couple of the old base level minis for a DTP shop back then (more RAM / IO bound than CPU). They allowed for installing 16GB of cheap commodity RAM and 2x 2.5” drives which netted you a decent 1.5 TB Fusion Drive. Good days. Today, with improved vendor lock-in for essential components, you’re looking at 2k+ for an equivalent spec. No thanks :)

The RAM is user upgradeable, and an external SSD drive connected to TB3 is not going to exactly be slow.

If you are so inclined you can use an eGPU something you couldn’t do on any previous Mac Mini.

That was 4 years ago, so that was probably as reasonable an amount of memory as 8 GB is today. And the Macbook Airs start at a 1.6 GHz dual core, so Apple isn't above using slower processors in new products. It'll work fine for some people.

The SSD is non-negotiable today though, I'll give you that one.

4Gb is good for a media server and not much else.

Between memory compression and very fast SSDs, I bet you could do it. Especially if you aren’t running a bunch of Chrome/Electron stuff like developers tend to.

Of course a lot of the target market for Macs like that would be better served by iPads now.

The 4GB Macs in question were using slow 5400 rpm hard drives.

But, until two months ago, I was using a circa 2009 Core 2 Duo 2.66Ghz laptop with 4GB of RAM with an external USB drive running Windows 10 as a Plex Server. It could do one or two streams depending on the bit rate. It could not do a 4K stream.