Marketshare is only one factor. In mid-late 2000s, you could have pushed users to install Firefox and then Chrome and say IE is not fully supported, didn't work

Marketshare is only one factor. In mid-late 2000s, you could have pushed users to install Firefox and then Chrome and say IE is not fully supported, didn't work with enterprises but for captive audience and startups it made sense. Now that isn't an option as users can't migrate away from Safari. So, it is worse now, Safari will decide the baseline and if it doesn't support some feature that you need, you'll have to let go richest x% customers or move to the walled garden.