This may not be an option for all users, as older Macs may have already been upgraded to the highest available version of the operating system, OS X 10.9 Mavericks, forcing them to look at alternatives such as Apple's own Safari web browser or Firefox. What this means is, unless the macOS is updated to at least Yosemite, then Google Chrome will no longer be able to be used. If you happen to be running a version of the OS older than Yosemite, you'll encounter the following error when attempting to launch Chrome. The latest automatic update released for Google's popular web browser has nudged up the minimum operating system requirements to 'OS X Yosemite 10.10 or later' for macOS users, as per the Chrome browser system requirements page. Now, it appears that machines running older versions of macOS have been frozen out of receiving further Chrome updates.
It was only in the last few days that it really came to light in a major way that Microsoft had effectively cut ongoing support for Windows 7 machines containing CPUs lacking SSE2, leaving users to either get a move on with a hardware upgrade or virtualize the affected systems as per Microsoft's recommendation.