I know what you mean, although I don't think it's always so cut and dried. As an example, locally, I'm involved in a missions education program that is multidenominational, and one of the primary leaders is a member of the Presbyterian church. So I think the picture is, although something along the lines you've mentioned in general, that there are pockets or factions within the larger groups that see evangelism as a top priority without being compromising in regards to objective truth.
When I referred to a split between accomodationists and non-accomodationists, I was referring to churches that would be considered evangelical. Bill Hybels is clearly in the accomodationist camp; John MacArthur clearly is not. Generally speaking, the non-accomodationist group comes from Southern Baptist, conservative Reformed, and dispensationalist ranks. This group includes most of the intellectual defenders of Christian doctrine and worldview: Sproul, Geisler, MacArthur, Ankerberg, Haanegraff, et. al.
The mainline denominations had fallen into the grip of higher criticism, the Social Gospel, and liberal theology at the national level and in the seminaries by about 1940. Providentially, most of these denominations had conservative survivals, often in areas where the denomination's regional leadership did not buy into the full liberal program. Karl Barth's movement from liberalism to what was termed neo-orthodoxy was influential and drew some ministers and seminarians away from apostasy back to historical Christian beliefs.
Therefore, it is not surprising to find some mainline ministers preaching the Gospel in spite of denominational demands for political correctness and left wing social action.