Why is JavaScript so slow on my Samsung Galaxy Tab S3?

[Android Central Question]

On general benchmarks, like Antutu, my 2018 iPad is just about 30% faster than my Samsung Galaxy Tab S3. But some JavaScript-intensive sites seemed very slow to me, so I ran the JetStream JavaScript benchmarks, and my iPad was almost FIVE TIMES faster (A score of 168 for the iPad/Safari vs. 34 for the S3/Chrome).

This seems crazy to me.

Should I suspect that there's something wrong with my particular S3? Is it just that JavaScript in particular isn't well implemented for Android, or for the Snapdragon processor?