The Catalina OS seems to have a number of glitches or disadvantages for a relatively inexperienced and text-based user like me (loss of Office Suite, greater emphasis on graphics amongst other concerns).
How long will Mojave be usable before it is phased out completely?
MacBook Air 13", macOS 10.14
Apple does not phase out operating systems. You can continue to use Mojave until your computer fails at some point. There is a three-year, sliding update schedule for Apple operating systems, so right now, Mojave will receive Security and browser updates for two more years. Microsoft also follows Apple's support window, so in two more years, you will not be able to install a new Office for Mac distribution on Mojave.
Catalina is a new operating system, and is expected to receive several more updates in 2020.
Your Office for Mac solution ceased to work with Catalina because it is a 32-bit, Microsoft retired Office suite, and Catalina requires the newer Office 365 (subscription) or a single purchase license for Office 2019 for Mac. These are 64-bit solutions currently receiving updates from Microsoft.
There are contemporary, non-subscription applications, for under $100USD in the Mac App Store, that can replace any older 32-bit Adobe applications that existed prior to Adobe's subscription program.
Apple does not phase out operating systems. You can continue to use Mojave until your computer fails at some point. There is a three-year, sliding update schedule for Apple operating systems, so right now, Mojave will receive Security and browser updates for two more years. Microsoft also follows Apple's support window, so in two more years, you will not be able to install a new Office for Mac distribution on Mojave.
Catalina is a new operating system, and is expected to receive several more updates in 2020.
Your Office for Mac solution ceased to work with Catalina because it is a 32-bit, Microsoft retired Office suite, and Catalina requires the newer Office 365 (subscription) or a single purchase license for Office 2019 for Mac. These are 64-bit solutions currently receiving updates from Microsoft.
There are contemporary, non-subscription applications, for under $100USD in the Mac App Store, that can replace any older 32-bit Adobe applications that existed prior to Adobe's subscription program.
FWIW, You can update Microsoft Office to a Catalina compatible version or use LibreOffice which is free. Not sure what you mean by more emphasis on graphics.
As far as how long, at least 3 yrs I would think.
Catalina OS and life span of Mojave
