Actually, the movies (where the bridge was redone, the uniforms changed, the ship changed, etc) are what got people to watch. TOS was... canceled.
Nope. TOS reruns is what got people to watch. They went to watch the movies because they all knew the series.
And, you will note how everything (including the above-mentioned categories) has been changing as the years have gone by. Why should the makers of the new movie roll back 40 years to keep everything the same or extremely similar?

Strange then, that the uniforms are practically carbon copies of the original series uniforms, aren't they? They went to roll back to 40-year-old characters, with 40-year-old uniforms! Everything stayed the same! How horrible! Now nobody will watch!
Quick, think of something! Ooh, iBridge saves the day! People will watch this movie ONLY because iBridge exists, yay!