I don't really mind the midichlorians stuff, but of course, the retcon is problematic, and more so, it was used poorly as only a plot device to show up Anakin. There have been rumours that the draft Lucas submitted for the sequel trilogy would (among other things) delve into the microscopic world. That sounds wild and new. Instead, Episode VII is basically just a rehash of the existing movies, particularly A New Hope and The Empire Strikes Back. The Last Jedi has no choice but to extrapolate from that, though at least it did try something different. (Which led to the backlash)