Is it ok to use in place of blindly?

Answer 1

As others have said there's a semantic difference between strong/b and i/em. Especially they are used by screenreaders for visually impaired people visiting your website. For them it makes a huge difference if you just make some text bold-face, or if you want to add some kind of EMphasis to what you're saying on your website. So be sure to carefully consider making something bold using B or STRONG. The same goes for EM and I.