It's their fault for having soo much riding on the success / failure of one movie. You never put all your eggs in one basket and that's exactly what they did making BvS and jamming all these heroes into the movie. They should've just stuck with the traditional tried and tested approach that Marvel had and built up their universe properly by taking their time doing the solo movies after MoS which is MoS 2, Batman reboot and the obvious WW solo coming up with little universe references in those solo movies, then JL. If feels as if BvS didn't needed to be made at all and this year should've just had MoS 2 in BvS' slot in March 25th and the Batman reboot in the SS spot in August.