Last I checked there were 4K comments under the trailer on YouTube and 1K dislikes posted. I'm sure it's even more if I check now for both.
The funny thing that people who really don't know about Sentai have no idea that the original Zyurangers that Saban based MMPR off of was not a kids show, in fact in Japan since it's insurgence of Sentai , the idea of Sentai was made to be a tv drama show for prime time viewers.
In fact Zyurangers was the complete opposite of the corny, campy childlike feeling of MMPR. One theme that Zyu stressed on was the overall abuse of little children in each episode. For those who were able to see Zyurangers know what I'm talking about.
If Saban followed the Zyu formula for MMPR, it would've never come off as a show for the target audience of children, so of course they had to make it corny and campy.
I think Bay wanted a balance between the MMPR theme concept for us fans but keep it dramatic for adults and children of this era to relate to it. Hence why this film showed a lot of teen angst and dramatic character development in just the trailer alone