Got a Mac with a SD Card slot? Don’t rely on it as a storage upgrade

Spinning disks are slow and solid-state drives (SSDs) used to cost a digital arm and a leg. That led many people to stick with hard drives or purchase Macs with low-capacity SSDs—like 250 GB or 500 GB—because the next increment up added many hundreds of dollars to the cost. (I’m sitting here with a 2017 iMac with a 1TB Fusion drive, so I am one of you.)If you’ve got an hard drive in your Mac or a low-capacity SSD, you are surely tempted to update your system, adding spee