I am not arguing that MS is any different, but any product that you purchased outright and is disabled after a period of time is incorrect. If it will run then you should be able to use it. I am pretty sure this is not the case here. MS Office 2016 ran for many years after it was replaced and only stopped working when it was no longer compatible with the OS. This issue here is with Office 2019 is a licensing problem that they introduced.Imagine if I bought a photo editing program digitally from another company that rhymes with whapple, for 499.00 at the time. then went to download it into a new mac after they discontinued the product and said NO. It's like I almost burned 500 dollars into nothing. Be speechless by this behavior, but don't think MS is the only one that has ever done this. Aperture falls into the same category only way more expensive. Oh, they discontinued it only one year later, not 7 years like Microsoft.
In the case of Aperture, it is an OS compatibility issue I believe, since I could download and install it for a number of years after it was discontinued but it studdenly would not download since it was no longer compatible with my OS. Aperture still shows up in my App Library, which in of itself is odd.