If we take what you said as fact it means that the "OS layer" is more standardized and more compatible between platforms. It means that we have a common target

If we take what you said as fact it means that the "OS layer" is more standardized and more compatible between platforms. It means that we have a common target that works for both FOSS users (FF/Chromium on linux) and for closed platforms (Edge on Win, Safari on OSX) and even the two large mobile platforms. In that way it levels the playing field and gives FOSS platforms a better chance. How many of the people who daily drive linux today do you think could have if the web was only a text/document consumption platform? At least in the group of people I know it would be far less.