Single-Directory Components (SDC) is the biggest change to Drupal theming since the introduction of Twig. Here's an "unboxxing" walkthrough of how it works.
We often end up with a lot of templates when theming, but we should also remember to create "sensible defaults", so before you start theming specifically your site doesn't look broken.
Here's an example of where "less is more" sometimes. I reckon we can make the video paragraph type in LocalGov Drupal simpler by just removing the template.
To the future or to the past, to a time when thought is free, to the next time when I need to get the value of file field to use as a variable in Drupal 8 with Twig.