Does Mohave 10.14.4 still support 32-bit apps?

This is a generic warning only. You have to do nothing, 32-bit apps continue to work on Mojave.

In the future release of macOS 10.15, apps will have to be 64-bit. App developers will issue updated apps if they want their apps to work on these future releases.

32-bit app compatibility with macOS High Sierra 10.13 ... - Apple Support

https://support.apple.com/en-us/HT208436

Yes. 32 bit apps will be dropped when the replacement for Mojave 10.14 is released.

Yes.

Yes but, that does not mean all apps are Mojave compatible, 64bit or not.

Welcome.