A pricing change was long overdue. AWS (which Heroku relies on to host everything) has been getting a lot cheaper in the last few years, but Heroku never changed its pricing and pocketed the difference.
It's only a price decrease for people with 4+ dynos.
If you really needed that 2nd dyno for performance reasons, then yeah, it's a price hike.
For 2 dynos the price increase is 44,9%!