I always subconsciously interpret the word 'modern' as 'in fashion,' probably because the word 'mode' means fashion in my language. I don't associate it with something good or advanced, but rather with something vain and ephemeral.
"Modern" as in "not repeating old mistakes" is good. It does not guarantee from making new mistakes, of course.
"Wow, modern" as in "very new, shiny, and surrounded by hype" is usually bad, because the emotions overshadow a rational view. This leads to incorrect assumptions, excessive optimism, and often to enthusiastic but incorrect application of the new and somehow worthy thing.
