When doing web work and changing pngs or jpegs, it is vital to keep the same file name so you don't have to go back into the code and change the file name again. Photoshop is not overwriting an existing jpeg when saving with the same file name, it's adding 'copy' to the end of the file name and saving a second jpeg file. This means I have to go find the file delete the one PSD would not overwrite and delete the word "copy" from the new file. It is really a pain and save a copy is not checked by the way so that is not what is going on. What gives. When you are in a production situation this is such a time suck. I hope you are not going the way of Apple with Final Cut and making it useless for actual professionals and dumming it down for the masses. So frustrating.
What are you saying this is not an Adobe Support Community? Adobe doesn't run this site? It is in the title and this is an Adobe URL. We are not supposed to talk about issues with the software? Then what is this for exactly. According to the home page, it says: "The Adobe Support Community is a place to ask questions, find answers, learn from experts, and share your knowledge. Because we are a community used by people of all ages, cultures, and people at work, we carefully moderate its content. Please help us keep them a safe and welcoming place for all members and abide by our Community Guidelines."
Not sure what is the point of having a support community if you don't ask about bugs.
As users, we are stuck in the same position as you. We can and do freely offer our experience, knowledge and advice. It is not possible for users to make changes to the software code, that is for Adobe to do. Users might have workarounds or be able to write scripts that bypass or workaround a particular issue until it is fixed by Adobe. In the cases of save related issues, I believe that affected users have been waiting for over a year for Adobe to fix the issues. Until the issues are fixed, scripting is likely the best workaround.
I believe the Problem is only on some Mac machine on Windows when you use the Save As Dialog and you enter in a file that exists Photoshop will ask if you want to replace the existing file and if you do Photoshop will overwrite the existing file. I believe on some Mac machine there is a problem the file saved will be a file that has copy added to the fine name. In Batch mode Save AS will add Copy to the file name there is no user interaction in a bach job.