Microsoft already offers a range of licensing agreements.
For companies who develop s/w that use SQL (Independant S/W Vendors (ISV's) they can sign a license agreement that lets them continue to ship their product with an older release of SQL. And they buy at a much reduced price, & so can make a margin selling SQL.
Larger companies with enterprise agreements or site licenses already have the ability to "downlevel" their s/w. As long as they have the media somewhere from their previous installs, they can continue to install the older edition.
For the smaller businesses they can go with the SQL that ships with Small Business Server. Same price, same version.
So that reduces the discussion to orginisations that only buy their databases &/or s/w as a one off purchases.
Like every other retailer, eventually prices rise. While you can sometimes buy older inventory it is only from retailers who failed to optimise their warehousing & only while stocks last.
So that leaves the question of: But what if I don't want all these new features? It opens the door to the age old question, should Microsoft sell little pieces of SQL as a set of optional add-in modules. That way you could buy what you intend to use. But it also creates a nightmare for developers who can't rely on the holistic feature set being there & increases the nightmare of licensing & auditing.
And if Oracle is anythng to go by, the some of the parts cost way more than it should as a bundle.
Perhaps a better question is, if I did change my app to take advantage of these newer features could I reduce Operations costs &/or make it perform better &/or could I make better decisions. Thus improving the value of that purchase. (It is my experience that most companies fail to use great features & spend vast sums recreating something equivalent to what is included in the product)
Don't get me wrong, I dislike price rises. But I do understand that Microsoft is a business, they need to pay their folks to develop the next release. And I am a consumer, if I can find what I need from another business then perhaps I will. Ultimately the laws of supply & demand will dictate price.
my 2 cents worth.