There has been some worry in the Apple community about the future of Office on the Mac since Microsoft announced that Office 2011 will no longer work on High Sierra. I think David Sparks nails it though:
I think a more likely explanation for the lack of support for Office 2011 in High Sierra is Microsoft's further efforts to push everybody onto their subscription pricing model and devote further engineering resources to the currently shipping version of Microsoft Office, instead of one six years old.
Office 2011 is 6 years old at this point and it only makes sense for Microsoft to continue updating it for so long. No app works forever, and given the multitude of non-custom stuff Microsoft is doing in Office, it’s not reasonable to expect these apps to work forever.
Besides, if you want to keep using Office and it’s not like Microsoft doesn’t make a version of Office the works perfectly for macOS High Sierra and is continually updated. You can get Office for a one time purchase like you always have for $149, or subscribe to Office 365 for $7/month. Sure, it sucks that software doesn’t last forever, but I wouldn’t make the mistake of thinking that dropping support for an old version of Office means Microsoft is throwing in the towel on us Mac users.
It’s worth noting that Microsoft does indeed support Office 2010 for Windows on the latest Windows 10 release. It’s not entirely surprising their own apps work longer on their platforms, but I could see what Mac users would feel a little burned they are not getting as much love.