Podium Walker was recently released for SketchUp 2021. This is Cadalog's CPU-based animation plugin. Podium Walker supports both Windows and Mac. Podium Walker is a good alternative to ProWalker GPU if you need to render fly-through animations, but use a Mac or do not have an NVIDIA graphics card capable of running ProWalker.
Podium Walker renders with your computer's CPU, so any computer that can run SU Podium effectively should also be able to run Podium Walker. Read more about Podium Walker here.