It's like one day someone decided that every interior design professional should act a certain way. That certain way is the only way you are allowed to act. Or else? You're kicked out of the club and off the island for being "unprofessional".
There's lots of ways to blog. And while you could just share images of your pretty designs there's something to be said for writing content rich interior design blog posts. Badass interior design blog post ideas that will get people hot and bothered to comment, share and fall in love with you.