The Retina MacBook Air was refreshed last week with a new price and the addition of a True Tone display. The refresh was minor, with the same CPUs as 2018, but a $100 cheaper price point: the 2019 MacBook Air starts at $1099 from Apple, with $999 student pricing.
It turns out that one downside to this latest revision is that the laptop actually features slower solid state storage than the 2018 model.
As tested by Consomac using the Blackmagic Disk Speed Test, the 2019 MacBook Air can attain read speeds of 1.3 GB/s read and 1 GB/s write performance.
The equivalent 256 GB SSD 2018 MacBook Air could top 2 GB/s read and around 0.9 GB/s write speeds. Therefore, the new SSD component in use has marginally superior write speeds but 35% slower read speeds, falling from 2 GB/s to 1.3 GB/s. (The 128 GB SSD option has slower 0.5 GB/s write speeds, but this drop-off was also observed in the 128 GB 2018 Air.)
Presumably, the slower SSD is a cheaper component for Apple to pack into the machine and helped the company achieve the $100 price drop, and even more aggressive education pricing for students.
In truth, this compromise was probably the right tradeoff to make. The lower price will make the machine appeal to dramatically more people, and disproportionally few MacBook Air users will notice the slower SSD read speeds in normal usage. A 35% slower SSD does not automatically translate into an overall performance loss of 35%.
A 1.3 GB/s SSD is still sufficiently fast enough that most heavy computing tasks performed on the Air will be primarily pegged by the CPU or GPU or RAM constraints, making the additional SSD speed overhead a little superfluous. Of course, it will be slower. But for typical laptop needs, it should be just fine.