In one line
An account whose owner has proved they control it. Influcius calls it a proven account.
On Influcius a creator proves an Instagram or YouTube account by putting a code in its bio or channel description, and Influcius checks it.
It proves control of the account. It does not prove the person's identity, the quality of the audience or the work. It is also not the platform's own blue tick.
Agree: nothing: check the proven mark, then judge the work.