Digital Content Strategy should be audience-based: your hashtag strategies should also vary according to your project and goal. Digiday recently posted on why companies like Chobani purposefully overuse the #hashtag on Instagram. If you are posting for a millennial brand, I advise being very liberal with hashtags unless you are targeting a subgroup within Generation Millennial like Style Influencers or Journalists who see hashtag over-use as potentially déclassé. Consider using the 80/20 rule with hashtag overuse on Instagram
Remember that hashtag overuse on Twitter is significantly less cool.
I posted this Instaglam pic of me having dinner with my cat, and was lenient with my hashtag use because I am actively growing my brand on Instagram; I reach out to Style Influencers on Instagram through honestly commenting on their posts, and I am less concerned about the 20% of them who might actually notice the fact that I even use hashtags.
Please share your take on hashtag overuse, and enjoy your day!