The problem raised when Web Developers failed to follow software developer principles few years ago. The just develop a page and test it with Google Chrome not because Chrome was cool during those days but because they simply think Google is good so Chrome is good too. Then users complain why the website is not working with Internet Explorer and they add banner that it is recommended to use Chrome. Some third-party applications also forced Google Chrome, remember when we wanted to update or install some legitimate programs, they have checked box and it has been checked to install Chrome and make it default? If some call themselves web developers, they know they have to test their product before release and it is normal to test with well known browsers including Internet Explorer.
Time past and people switch to Chrome, now if someone is using Windows 10, I strongly recommend them to use Microsoft Edge as their default browser in term of security it is superior than both Chrome and Firefox and I am asking web developers to test their website with Microsoft Edge too. This shows professionality of developer , to show their clients we are supporting them and we won't force them to use specific browser. It is not professional to force user to switch to Chrome from Microsoft Edge because developer is lazy and don't want to do proper testing. I agreed in case of Windows 10, use Microsoft Edge and switch to Internet Explorer if you want to. However, you have to take a note that support for Windows 7 will be ended on January 14, 2020 and support for Windows 8.1 will be ended on January 10, 2023. Meaning, even they are on extended support. We have to make sure that all websites working great on Internet Explorer 11 and they have their functionality , while we concentrate more on Microsoft Edge and modern standard.
Microsoft has been leader in software development and web browser and I don't like to see indirect advertisement of competitors. Anyone is free to use any browser as they wish, but we as Microsoft Expert must be make sure users are having great experience with Microsoft Edge and Internet Explorer. So to clarify this while we need to move for new standard and make sure we use full potential on Microsoft Edge. We have to make sure our websites working great in Internet Explorer while it is the only Microsoft supported browser in Windows 7 and Windows 8.1. There is news of upcoming version of Microsoft Edge which would work on Windows 7 and Windows 8.1. However, we could only stop testing Internet Explorer when we make sure Microsoft Edge for Windows 7 and Windows 8.1 has been released and is stable version. Don't forgot that the only browser for Windows Server is also Internet Explorer. We know that people won't use Windows Server to browse website but you should consider this case that there might be certain cases when web administrator need to get certain data from your website and it doesn't feel nice, if you tell them sorry Internet Explorer is not supported.