The biggest cause for the negative response to Dragon Ball Kai nostalgia and what I mean by that is there are many elements to Dragon Ball Kai that have been changed from the original series. Many fans did not like that the music had been changed; how some of the voice acting was different; or how they changed lines around. These changes were surprising to many fans and they felt it took away from original feeling they got watching Dragon Ball Z. That left Kai with a tainted reputation and made it hard for it to pick up momentum and gain popularity among to original fans.
Many fans have only seen the Nicktoons version of Dragon Ball Kai or other censored versions floating around online. This caused many people to believe That Kai was meant for little kids and it lacked the original blood, violence, and bad language once seen in the original. However, that is not what Kai is all about. There is an un-cut version of kai which contains all the original blood and violence; it even contains more foul language than the original series. The un-cut version of Dragon Ball Kai is even making its way to Toonami, in November 2014. This will expose more fans to the original version of Kai that was not meant for children.
In the original Dragon Ball Z series there are many episodes that are not from the original author Akira Toriyama. These episodes are known as “filler” episodes and were made to entertain viewers while Toriyama was finishing up chapters of the manga. Often times these filler episodes strayed away from the original story arch; which in the eyes of many fans is not a bad thing. In Dragon Ball Kai the filler episodes were removed and only the original episodes were shown in Kai. This left fans feeling like there was a lot missing from the show, but what they were actually seeing was the original story line written by Toriyama.
Why Dragon Ball Kai? Dragon Ball Kai is essentially an updated version of the original series. The original series was dubbed in English by Funimation, and at this time Funimation was a brand new company. Their lack of experience resulted in the original series not being produced as well as it could have been, so by coming back and re-dubbing the series Kai actually has much better voice acting and a better script. However, all of the upgrades and enhancements that have been made to the series are not what makes kai an excellent series; what makes kai an important and amazing show is that it has brought Dragon Ball Z to an entirely new generation. Dragon Ball Z is a very old series and was running on fumes, but with the release of Kai, Dragon Ball Z has begun to make an amazing comeback. With the release of Kai and other new Dragon Ball Z related media a new generation of fans has been born and hopefully that fan base will continue to grow for years to come.