Funny you mention that because I hated Superman prior to MoS. That movie gave me a lot of respect for him.
I kind of agree with this. As much as I love BvS (its flaws actually make me love it weirdly), BvS would've worked insanely better as a DCEU film 7-8 years into the franchise. Batman's distrust for Superman, driven over the line by how long he's been in Gotham makes sense for an older Batman... but it was too soon. Superman's death/ no Green Lantern yet would've been the perfect setup for an Endgame style JL film, keeps the audience guessing for who the savior will truly be at their most desperate hour. Alas, I still like a lot what we're given, and I love that each movie here has its identity, but Snyder and WB messed up with communication, as Snyder intended this franchise with a specific start - end while WB wanted to expand it.
I do think character building is needed as well and I appreciate Snyder trying to make Superman that way (from irresponsible in Man of Steel, realizing the weight of the world in BvS, and suppose to be the symbol of hope in JL), but again, the setup and execution weren't timed correctly.