It's 60% faster (0.6x faster, 1.6x as fast). Throughput (“how much stuff you can do per unit of time”) is the only reasonable way to describe performance[1], otherwise large speedups are basically impossible to describe in an intuitive way. (If something that took 10s now takes 1s, that's “ten times as fast”, not “zero point nine times faster”.)

[1] Even latency changes are best described in terms of throughput.

The problem is that “faster” and “slower” compare speed, which is x units per y time. But here, we’re only comparing time. The semi-legit interpretation is “if one unit takes 22.2ms, how many units can I complete in 35.6ms”, and actually the answer to that is indeed the 1.6 number they mention.

It’s not sensationalist, it’s just a bit sloppy with the word “faster”.

1.6x faster is completely acceptable in natural language.