March 2021
I just got back to origin and downloaded sims 4, (legacy, because my mac is too old for the new one to work). I have sims 3 too and I want to download it but it won't work because the 64 bit update isn't in my library. I have tried contacting EA so many times the last week and there's always an "error" with the call system and they don't email me back! This is so tiring at this point. I also had almost all the sims 3 expansions so it feels like they just don't care about their customers. I just can't believe I have been trying to contact them for a whole week with no response.
March 2021
@mariim19 If your computer can't run the standard version of Sims 4, it can't run the 64-bit version of Sims 3 either. Both require that your Mac support Metal, and the minimum operating system for 64-bit Sims 3 is actually newer than for Sims 4.
If you want to double-check whether you can in fact run 64-bit Sims 3, feel free to post the specs of your Mac: everything under About This Mac except for the serial number.