Again everything you said could be true.... doesn't matter.
Could be true? You provided the information, not me. You posted screenshots of a 2016 plan and a 2017 plan that both clearly list the same premium, +/- 4 cents. Looks like premium growth in bronze plans in your area was zero this year.
And, based on the fact that your subsidy shrank, it sounds like premiums for silver plans in your area actually dropped. Unless the reason for the falling subsidy is that your income increased.