This looks pretty good. Though scaling in browsers has been mostly independent of corresponding OS features for quite a while. E.g. the issues mentioned above with Linux and fractional scaling do not affect browsers as much. The problem is usually with native UI elements, such as the settings app itself.

However, it is unclear to me what are the scaling ratios relative to the native resolution in your examples. In this article for Sierra you seem to be only able to pick integer factors: https://www.eizoglobal.com/support/compatibility/dpi_scaling...