The solution to faulty programming is what wait a year and hope they finally fixed the game to where it is reliable enough to save a game and expect it to work the next day? I can not fathom how anyone can defend this.
Because people that are used to playing grand strategy 4x games of this nature know from experience that a patch always runs the risk of being incompatible or messing up previous game saves. Your game would have worked the next day had you not updated it. They are changing the data those games reference, in ways that simply might not work with a new rule change. It is the nature of the beast. If it's not something you can live with, stick to first person shooters and platform jumpers.
Should they have issued a bigger warning in the patch notes? Probably. But this is a lesson you had to learn sooner or later, the same way toddlers learn not to touch a hot stove, and new computer users learn to save their work *often*. Don't update your game if you are attached to a game in progress. Don't upgrade your software, and *expect* complete backwards or forwards compatibility. It's nice when it happens, but it isnt guaranteed.
I'm not cursing out the devs or wishing a plague of crazy cat women flinging tabbies on them. All I ask is when a game comes out of beta and is in retail to be able to save a game and expect it to work the next day. I hardly think that is an unreasonable request or "childish" in asking for.
As explained above, it is an unreasonable expectation in games of this sort, and you continue to express it in a caustic, childish manner. The devs are continuing to work to make fixes and improve the game. Some of these are going to be significant enough to actually change the rules of the game, and become incompatible with previous save games. It is a risk with any patch. Don't patch if you're in the middle of a game you don't want to take that risk with. Let us know how many times you want to be able to make the same mistake, and then blame the people who are trying to improve the game for you.
If it means fixing and improving the game, I hope the devs break save games with every patch, every day for weeks. I am grateful for the timely effort they are putting into addressing player issues.