Here they have compressed about 15hrs of the TV show into just 1.5hrs, because of this they have edited the story ruthlessly and even changed it a fair bit. And most importantly, it just did not have the time to give the back stories of more than 10 important people! They were disposed off so fast that it felt rude to the ideals they represented.
They even changed the behaviour of some people. Kaoru who is just a teenage girl hopelessly in love with Kenshin; rash, tomboyish and unlady like most of the time was behaving and talking like an elegant mature lady!
Its because of all this that people who saw the TV show got disappointed and gave it such a bad rating.
But if you were to see it without prejudice it's a great 8/10 anime. Especially in the 1st half, I was constantly wowed by the excellent animation and the pacing was just correct. Please disregard the ratings and check it out yourself.