Rescaling is extremely efficient and not a problem. The reason macOS doesn't support arbitrary DPIs is because it's so hard to design the UI correctly to avoid

Rescaling is extremely efficient and not a problem. The reason macOS doesn't support arbitrary DPIs is because it's so hard to design the UI correctly to avoid things like pixel cracks; if you make everything to look like a website, don't use bitmap images, etc it's possible though. Instead it has dynamic type, which changes text sizes but not the rest of the UI scale.