Pretty much. Why, you will make excuses so hard, you will attach eye-rolling emoticons to them in the vain hope that it will conceal the painful stench of sour grapes in everything you say and do.
Anyway, I dunno, I sympathize with someone who's sat through 42 episodes, didn't see anything like this coming, and can only feel betrayed by Shinkenger over this twist. That's not how I feel, but I can see where someone like that is coming from.
The show wants you to like the individual Shinkengers. You sit through this **** because you like the characters (if you didn't you'd have better things to do). So you get attached to Takeru, you sympathize with his struggles, maybe you really get into the idea of a Red who is like a modern feudal lord.
Then you get to the end of the show, and... oh, by the way, he's a liar! Here's the real Shinken Red, someone you've never seen before even though we're six episodes from the end!
Whether the replacement was male or female, some people just aren't going to be cool with that. Especially if you're a viewer who outright enjoys Super Sentai's formulaic and predictable aspects.