> it surprises me that this hasn't been perfected

It shouldn't. It's never really been perfected across native GUI APIs after 40+ years: just various degrees of "good enough," plus fobbing it off to web stacks.

Anyhow, I've been playing with gioui, which is golang rendering in a lightweight <canvas>-like. Really nice: fast, small, cross platform GUI with just Go. Scale expectations appropriately.