I already posted a lot of these points on the Power Rangers thread but since that I've learned a lot more, Panda Khan has also been right in all his posts, so I"ll break it down to points below but for the TLDR: Hasbro bought more than just PRs and yes TMNT could've sold for more.
*Peter Laird likely sold TMNT for "cheap" (60 mill) to get out, also TMNT had no future plans, if he head shopped around more maybe he could've gotten more interest, especially if TMNT had future plans.
*Saban Brands bought Power Rangers from Disney for 100 million, Disney likely sold cheap since they didn't want to deal with Toei anymore and had just bought Marvel
*Saban Brands had 500 million in investment money, they bought many other brands including Julius for 50 million, Popples, My Pet Monster, rights for animes etc. Also Power Rangers still has a 3 year Nickelodeon deal
*Hasbro bought all of Saban's Brands, Power Rangers just happens to be the biggest one but between what Saban spent that we know it was already 150 mill from just PRs and Julius, surely the other brands were cheaper but they add up. With this in mind it's no longer "500 mill for Power Rangers!!1"
*Power Ranger has been on the air for 25 years with toys on the shelves always, they've had good and bad years but have been #1 boys best seller many years including when 2k3 was airing. PR does have wider appeal worldwide. TMNT was only ever a huge hit with the OT, 2k3 was successful but those two shows can't match PRs over their whole time.
*Hasbro wants to make their cinematic universe a reality and besides GI Joe/Transformers they have no real big brands. This deal gives them nearly 900 episodes of PRs among other properties that also have shows (VR Troopers.
*Even though they spent 500 million on Power Rangers, they still don't control the property, Toei has a big stake and basically co-own power rangers and can shot down any crazy ideas Hasbro may have
*This means Hasbro officially owns Ninja Turtles: The Next Mutation, which is not new to Hasbro since when they had their channel The Hub The Next Mutation also aired with other Hasbro cartoons.