This pop-up keeps popping up: "“Adobe Reader” is not optimized for your Mac and needs to be updated"; only since I have been running MacOS Mojave. . . something about 32 & 64 bit. . . whenever I try to update Adobe Reader, it's up-to-date. I subscribe to Adobe CC full version, so I don't think I need to be taking this seriously, but I'm not sure. Is it only a matter of dis-installing an out-of-date Adobe Reader app, or is it a bug or a phish? Thanks.
Acrobat and Acrobat Reader are already 64-bit on the Mac and have been for 3 years. I suspect you are running a really old version, because you still call it Adobe Reader, and that name is no longer used. Please check the exact version you have, and let us know.