Agreed. I love my translation (ESV) alongside many others but inserting this as a section header is wild and poor exegesis. Many other cases like this.

1st, there are two full sets. Exodus 20 reads a bit more like a decalogue, but Deuteronomy 5 doesn't; it's a prologue of sorts into the Torah. 2nd, impossible to break just one. By breaking any, the first - no other gods - is broken. a cohesive set. Deut. 5:30 refers to the "the whole commandment" - singular. (con.)

Fourth, the pericopes (the section headings) in Scripture, while I believe they are divinely guided, they are not at the same level as the rest of the text, and are meant to aid in a cursory reading, but not intended to guide deeper study - the text itself is the "meat".

Lastly, and more importantly IMO, the 10 commandments are not the entirety of Judeo-Christian living. Both texts (OT & NT) are clear: loving God (no idols) and loving people (seeking Harmony - aka shalom) are the primary directives for what it means to be a human in alignment.