Your LinkedIn profile takes on a more informal tone because employers understand it to be a personal profile, so it's okay to use «I» in your writing. (gotthejob.com)
Some readers might find it difficult to engage with the chatty, informal tone of the letters which can occasionally come over as slightly forced. (faith.org.uk)
As a reader, and an author myself, who takes pride in smart use of language, this is a refreshing change of pace from the more informal tone most books these days employ. (talkinganimaladdicts.com)