While the series like to stress that Both Sides Have a Point, it has proven to be rather contentious if the show has gone overboard in overexaggerating Daniel's flaws and "fault" in his past conflict with Johnny. Notably, the scene where Daniel recounts the incident when Johnny and his friends almost ran him over with their motorcycles and drove him off the road gets Played for Laughs, and Daniel's own experiences at the hands of Terry Silver (which had a more significant impact on him than Johnny's actions) also seem largely overlooked until Season 4.
In Season 1, Daniel's response to Johnny spraypainting a penis on one of LaRusso Auto's billboards is to manipulate Johnny's landlord Armand Zarkarian into raising his rent. It's clear that Daniel was so focused on getting back at his former bully to the point that he failed to see how his actions were negatively impacting others, and he gets called out on it by Amanda. For some, Daniel's actions were disproportionate, while others view Daniel as justified in responding, noting that Johnny's vandalism could have tarnished Daniel's business image/branding (especially with Tom Cole trying to poach business from him through ads that made indirect digs about Daniel's business being unpatriotic and environmentally irresponsible) and gave Kyler more ammunition with which to slut-shame and bully Sam at school.
Sam's Freudian Excuse Is No Excuse remark regarding Tory of "Everybody's got a sob story. Doesn't give you the right to be a bully" is divisive. To some, this is an Innocently Insensitive remark with Sam putting Tory down because of her lesser financial status. To others, Sam's words are perfectly justified because Tory has been a bully towards her, between her tripping Sam unprovoked at the roller rink for talking to Miguel, and attacking her at school because of a drunken kiss, and as sad as her home life may be, it doesn't justify her actions at all.
The incident in "Pulpo" where Demetri shares some of Hawk's personal secrets to everyone at Moon's party has sharply divided the fandom. Either Hawk deserved it after he had bullied and antagonized Demetri and Miyagi-Do throughout the season and rejected Demetri's attempt to reconcile earlier in the episode, or Demetri revealing private information was taking things too far and the act was disproportionate compared to Hawk pouring a drink on his head.
Demetri defeating Hawk in the school brawl in the Season 2 finale is seen as either an awesome Throw the Dog a Bone moment for the show's biggest Butt-Monkey and a healthy dose of Laser-Guided Karma for Hawk, justified by the latter's arrogance and underestimation of the former's improvements at karate, or an Ass Pull that ignores the gulf in skill and experience between them for the sake of giving Miyagi-Do a cheap victory and undermines Hawk's ability to be taken seriously as a threat.
Aisha being written out of the show. Some fans felt that the in-universe reason given in Season 3 for Aisha's departure is actually very realistic, as almost certainly a number of parents would withdraw their kids and send them to other schools after an incident like the school fight. This side has overlap with those who feel Aisha was due to leave the show, believing her arc had largely concluded in Season 1, she was mostly taking up space in Season 2, and that if she stuck around for Season 3, her arc likely would've been so similar to Hawk's as to make it redundant. And there are those who feel They Wasted a Perfectly Good Character and that the show could've done more with Aisha without pushing her out of the way to make room for Tory.
Hawk's Heel–Face Turn in the Season 3 finale. It's proven rather contentious whether his redemption was earned or not. While the seeds of his Heel Realization was planted throughout the season (as Kreese kicked out Bert and Mitch, and the latter specifically got replaced with Kyler), it's still a matter a debate over whether his defection in the final episode came too quickly or is enough to make up for the numerous crimes and bullying he'd committed against Miyagi-Do students during Seasons 2 and 3.
Season 4's efforts to humanize Tory and Kreese and make them more sympathetic to the audience have proven rather divisive. Many fans enjoy the additional layers given to both characters and appreciate the effort to return the series to the Grey-and-Gray Morality that was employed during Seasons 1 and 2 before Season 3 made them more straight up villains. Other fans feel that the characters' actions in the Season 3 finale, particularly Tory breaking into the LaRussos' house and siccing Kyler on Miguel after he had just regained the ability to walk and Kreese trying to outright murder Johnny and Daniel, were just too heinous for them to garner any sympathy after the fact and the two of them work better as straight villains. This has somewhat calmed down after Season 5 which did a more substantial job redeeming Tory (while also giving her some indirect karma for her previous misdeeds) and confirmed that no amount of humanisation is actually enough to redeem Kreese.
Carmen becoming pregnant with Johnny's baby caused significant division in the fanbase. While many are happy that Johnny, Carmen, Miguel and Robby will each eventually have a new member in their family, and believe this to be an acceptable continuation to each of their character arcs, others have been critical of Season 5 seemingly playing the Babies Make Everything Better trope completely straight, largely because it takes away from Johnny's attempts to rebuild his relationship with Robby. Detractors have also argued that Carmen having another baby - and it being used to bring the family together - has the potential to do more harm than good in the long run, to say nothing of the message it has the potential of sending in regard to toxic dysfunctional families.
