yeah, 2 words...
TW no longer have unrestricted control of their own product. I don't care what they publish or say officially, a big company doesn't agree to invest in and market a product without a strong control of what happens to it and with it.
There is far more money to be made from pumping out three or four games, with minor issues, than from creating one masterpiece. If we all paid US$15 for a M&B bugfix/upgrade patch, it would be different, then we might see some support and development of the original game....
It's what happens when games are made for profit and not for fun, and from one point of view quite obvious and logical.
Lucky for us players there are mods like yours!