Same here, I don't like using a laptop except where I have to. I have a 2015 and 2017 top-spec iMac 27, also a 10-core Vega 64 iMac Pro, 2016 MBP 15 and 2019 MBP 16. The 2015 iMac by current standards is pretty slow. When I get my M1 Max MBP 16 I'll run various benchmarks and real-world tests and post the results.Right now that new MBP with M1 Max is very tempting for me, I need a new compute that can handle 4K to 4K rendering that calls for heavy GPU computations like Noise Reduction. I don’t want to buy an Intel Mac Pro or for that matter a 2020 27” iMa… One thing is for sure that M1 Max MBP will blow my 2015 iMac out of the water… I however have a fundamental issue with using a laptop as a desktop…
Exactly as you mentioned, need for high CPU/GPU performance is not limited to 3D graphic artists. For those who say "who could need that much performance", try running Neat Video on 4k clips or Resolve face refinement or Resolve Magic Mask or Digital Anarchy Flicker Free or Imagenomic Portraiture. Those will bring almost any machine to its knees. Those are not exotic tasks but are very typical when finishing a video.
You probably saw the rumor on this site about an M1 (likely M1 Pro/Max) iMac 27 early next year. For those needing a more powerful updated desktop that might work.
So far the leaked GPU GeekBench numbers on M1 Max show it's a bit faster than the Vega 64 GPU in my iMac Pro. That is amazing for a laptop but my iMac Pro really bogs down on some of the above-mentioned tasks. That said the Apple "Unleashed" video showed a brief statement from a DaVinci Resolve developer who claimed M1 Max could run Resolve Magic Mask (sort of an AI rotoscoping tool) in real time, which implies without rendering to cache. If so that's great but I'll believe it when I see it.