Software that is not COMPATIBLE with Catalina

Isn't it more useful to say that if an app worked on Mohave 10.14.6, it will work on Catalina? (Or is that not correct?) When I used the roaring app, it just showed question marks over the whole range of recent OS versions for my apps I have been using right along to the present.

Isn't it more useful to say that if an app worked on Mohave 10.14.6, it will work on Catalina?

No because that's not the case, especially as Catalina no longer supports 32-but apps.

When I used the roaring app, it just showed question marks over the 
whole range of recent OS versions for my apps I have been using right 
along to the present.

Then update that database. It's crowd-sourced and you could help make it better.

Much better if you ask us about specific apps that concern you. Naming them all would take forever.

In general 32 bit apps aren't compatible.

https://roaringapps.com/

maintain a list

As mentioned in your other post, check for 32bit apps. None are compatible with Catalina.