Let's debunk this. There has never to this day been a reasonable debate over corruption changes. The supposed "support" for the new changes comes entirely from people who are upset that the person is attacking the game developers, and/or from people who admittedly never encounter it. You may be upset at the open hostility many players have let loose over this issue, but understand the main reason why these players might be so angry: they're being told something is fine from people who have an entirely uninformed opinion.
Every game that in this and neighboring genres has to answer the question of how will expansion be penalized. The two theoretical extreme positions to the answer are:
Double the land, double the strength
Additional land is never worth it
Now for obvious reasons either of these extremes is bad. In the first situation you quickly snowball out of control, and the game becomes trivial after a war or two. On the other hand, additional land never being worth it kills the motivation to expand, which is the main motivation behind the game. Even small indie studios understand this and pick some kind of middleground option usually incurring temporary penalties, such that the land acquisition isn't worth it in the short-term, and acquiring too much of these short-term penalties can stall your country entirely.
EU4 5 years after release has suddenly gone with the 2nd option. There's a number of states/territories "X" that once you exceed it you receive an unnegotiable penalty that makes the addition of all territory after X bad. The cost you pay to buy down the corruption is always more than the profit from the territory. This isn't because of some strategic "you took land you weren't supposed too lulz". It happens with any land after you have X states. This is quite possibly the most embarrassingly bad gameplay decision PDX as a company has ever made, on any game. It's a completely asinine answer to a question that many companies, PDX included, have already found better solutions to for the past 20 years. It's the equivalent to DDRJake making a dev diary claiming to have reinvented the wheel and the new shape is square.
Yes there are "loopholes" such that the above reasoning isn't absolute. Currently that loophole is to either rush TC land or vassal storm. The two strategies that were already the most OP in the game now become mandatory. It's also worth noting there is actually an upper bound # of territories "Y" where additional land suddenly, mysteriously, no longer has an additional corruption penalty. This completely undermines whatever the supposed reasoning behind the corruption penalty was to begin with. It also means there is a number of territories, "Z" such that finally you've made a long-term profit on states acquired after X. The difficulty is ofc getting to this Z value. Right now the way to afford it is TCs. You haven't added "strategic decision making" in expansion routes, it's been railroaded to one single choice. New capital restrictions make the difference between Europeans and non-Europeans quite huge and yet based on a technicality. It also leads to fully bizarre issues where most Asians/Africans should prioritize an exodus ASAP, do some kind of trickery, or sit there and not do anything for 50 years until they can colonize Australia.