2dguy so...why not just stick with 32bit...assuming performance is acceptable???
First as 64-bit should be faster. How much exactly depends on the app but it’s noticeable and significant. Even without any changes (so just building a 64-bit binary instead of 32-bit) an app usually gets faster. With optimisations for 64-bit it can get much faster.
Second as the industry is moving to 64-bit. iOS is already there, macOS is almost there, Android is just starting the transition. Windows will be last, but there’s no reason why it won’t happen there.
In particular Windows comes in 32-bit and 64-bit editions; they can transition the 64-bit edition of Windows to just 64-bit apps while selling the 32-bit edition to anyone still running 32-bit apps. As with Apple, Google they would have their own way of doing it. Long before 32-bit apps are banned they could have warnings attached, be made to run at lower priority, be installed differently to other apps.