Yep!
I have a 2018 Macbook Pro and a pretty interesting/fun/skeletal eGPU setup made out of a Thunderbolt-to-M.2 adapter (intended for SSDs), M.2-to-PCIe adapter for the card, and a fanless 600W ATX power supply. I use it with an AMD 5700 XT and 6800 XT. Hooked up to a 55” LG OLED TV. It’s been very fun to operate.
It Just Works to a degree, and takes some tinkering as well. Quite a bit of tinkering actually.
The dedicated cards make windowing around in macOS snappier and smoother. It’s noticeable everywhere. IntelliJ is way, way snappier (it has Metal-based GPU acceleration these days.) The 6800 XT is noticeably smoother and faster than the 5700 XT.
For me, the responsiveness is worth it working as a programmer. 100%. Caveat: I enjoy the tinkering. Bought the setup to learn things and mess around.
Also, it’s a bit unstable. The GPU driver will lock up from time to time; I think it’s power supply fluctuations in my setup having a bad effect on a card running super tight video timing to push 4K 120Hz over a DisplayPort-to-HDMI-2.1 adapter. The wall power circuit breaker has too many devices on it (my fault). What happens is that the GPU or GPU driver sometimes locks up and the card becomes unresponsive and I can’t “safely remove” the device from the macOS menubar thing. When I unplug it, the Macbook Pro hard-poweroffs with a PFFFFT-gasp from its fans. It’s pretty clearly a systemic weakness. Might even be unfixable at the motherboard chipset level given how brutal the hard-poweroff is. –I’m not that surprised that they dropped support for eGPUs, given that adding support in their ARM M-series CPU platform would have needed some different core design decisions.
Playstation 3 emulation runs great, in macOS.
That said, if you’re biologically wired to be sensitive to responsive and smooth GUIs
everywhere, then a fast GPU works really well with macOS. What you really want if you’re like this is not an eGPU but an M2 pro or better with HDMI 2.1 output and an LG OLED TV. This gives you 4K at 120Hz, HDR, variable refresh rate, and super low output latency. Full viewing angle too. It’s magical.