But there aren't, there are performance advantages to reusing Nodes due to the specific way that browsers implement render reflow. If those implementations ever change, or you use React on a browser that doesn't suffer from implementation specific perf issues, you've introduced unnecessary complexity.

This is the type of rhetoric that is repeated without personal knowledge of internals or without understanding why the issue exists to begin with. You're basically saying that tree-based structures are inherently expensive.

Read implementing a browser a little. Read specs a little.