The Studio should be excellent. The needs of Archicad and TwinMotion are quite different... with TwinMotion relying almost entirely on the GPU. While Archicad will run in Intel emulation mode (Rosetta 2) for all versions prior to 26... at some point, we were told in a post here, 26 will run natively on Apple chips... a "Preview" version allegedly to be made available later in the year. (26 is not even announced yet as of this writing.)
TwinMotion requires a machine not only with a serious graphics card - which the Apple ARM GPU basically is - but with a serious cooling system as the machine will run quite hot when in TwinMotion. Again, the Studio should be excellent for that - other than that Epic does not fully support TwinMotion on Apple silicone yet. Some here have posted that TwinMotion runs fine for them though (Rosetta 2), so perhaps worth more investigation. This is thread discusses compatibility: https://twinmotionhelp.epicgames.com/s/question/0D54z000076FYxKCAW/does-anyone-knows-if-twinmotion-w...
One of the forum moderators • AC 26 USA and earlier • macOS 12.6.1, iMac Pro 10-Core, Radeon Pro Vega 64
As Archicad can run on both windows and Mac without major differences, i think its not the software that should dictate your choice of a new computer/OS. If rendering is something that you want/need to dabble with, don`t go for a mac. Cooling, hardware limitation and the flexibility for future options is quite limited. I heard (cause i didn`t have a change to test ) that M1/M2 are powerful, but i don`t think they will be the most supported hardware for game engines/render engines. Besides that...if you will ever try to at least test another software besides Archicad/twinmotion you will be surprised that a lot of up and coming softwares are not working on Mac. I would only pick a mac for portability, but for a desktop setup, i would always go PC.
All things considered, you know better what suits your workflow.
You need NVIDIA card to enable path tracer (i.e. gpu global illumination) in Twinmotion, which is the critical factor to me when choosing which computer system to use. You may want to run Archicad and Twinmotion on same computer, so Mac is a no-go (for me), although I recently purchased the M1 max laptop….