Who you are now is very different than who you were 10 years ago, and unfortunately, that's a level of nuance that internet crowds don't quite grasp. Yes, in hindsight you would go back and clear out your own content, but we all know that rarely happens.

Sure, but in three years, comments you made on Google+ when it opened will be ten years old. In fact, the fact that G+ is closing after 7 years highlights that it's death keeps your online presence somewhat current, whereas it's long-term preservation past that natural 7 year life will maintain it much longer than perhaps relevant and valuable.

It is impossible to know in advance all possible implications of an action or information. Especially at scale, whether of data, populations, or time.