To expound on my reply from yesterday, coring costs have gone up somewhere around 40% compared to 1.11 (more for dipannexation) because we wanted to create some more interesting dynamics where conquering everything around you was not necessarily always the best option.
It is still both possible and rewarding to expand, particularly if you take the right ideas, put money into advisors and use a mix of conquest and diploannexing. As Milan, I was able to unify most of Italy (more than twice starting development of France) in under a century without any core cost reduction, and could easily have done so faster. Growth is slower but it's certainly not 'blobbing now pointless'.
With that said, you are of course free to disagree, but this was an intended change and we knew it would upset some people, so we're not reverting it just because of one angry thread on the forums.