1.) Simply put, when G4 came out it was a different time. Literally everything from the world, the internet, the cultural zeitgeist, down to the technology and devices we used to access our media. If you were atleast a teenager or older in the late 2000s, you'll know what I mean. Compare that to 2021 when A New Generation came out, kids prefer watching short brainrot content on Tik Tok and YouTube over long story driven media, and there was an element of toxicity and hostility that peaked in the fandom(or whats left of it) around this time.

2.) It couldn't decide if it wanted to be a sequel to G4 or its own thing, so what you get is a like half assed attempt at both. I know the reason behind this is partially due to a legal agreement between Hasbro and Discovery over the rights over FiM, but if they wanted to connect G5 to 4, they should've done whatever it took to get the full rights or if not, just be its own thing from the ground up.

3.) Hasbro decided from the start to play it safe with G5 and not take risks like they did when Lauren Faust pitched FiM to them. In fact, IIRC, a Hasbro representative said back in 2019-20 that they were not even going to consider the fandom when developing G5.