I have always felt the actual ST:E theme is the ending credits.

Some producer got involved and decided they needed to "distance" Enterprise from the rest of the Star Trek franchise, and they also wanted to give it a bit more modern vibe so that it felt like it was between now and when TOS takes place.

So they took a Rod Stewart song from Patch Adams, changed some lyrics, and slapped it over what is arguably one of the best Trek opening credit sequences...