What do you mean “no improvement on macOS”? Most of the new features listed in these release notes could be considered improvements, and I assume that the macOS version of Firefox 67 has all those features, the same as on other platforms.
I think you had in mind a specific aspect of Firefox that you wished would be improved, but you forgot to explain what that feature was. What is the missing feature that leads you to use Chrome?
I think its obvious he's talking about the fact that Firefox is unusable on MacOS (on scaled resolutions). And it seems Mozilla has no ability to fix this for a large portion of their potential clientele.
I think you had in mind a specific aspect of Firefox that you wished would be improved, but you forgot to explain what that feature was. What is the missing feature that leads you to use Chrome?