That is not the full story.
Microsoft will still offer paid support for regular versions Windows 10 (and that includes security fixes)
There is also a long term support version of Windows 10 that will continue to receive free security updates for a few more years.
So, while I agree that using an unsupported OS to do anything critical (like paying taxes) is not a good decision, there are many ways to continue receiving security updates for W10 and dropping everything is just laziness.
