When I was still a university student way back in the late 70’s I was active in the Creationist Movement. Most of the folks took the young earth position and so that was to become the more or less official position for the groups active then and it seems to still hold true today.
Personally, I don’t think that accepting an old earth view helps Darwinism or really is the least unfriendly to the Biblical record of how things started. Certainly, if the earth was only 6,000 years old, that would put a damper on the amount of change that adaptation could produce. But, given the amount of pressure that exists for genetic conformity in nature (IE the “reversion to wilds rule” or mutants practically never make the cut), no amount of time really is ever going to be enough to enable “natural selection” or natural breeding to design anything resembling even the “primitive” forms of life we see today.
Breeders work hard to keep a gene pool healthy reducing inbreeding as much as possible and still maintain desired characteristics. Even so the percentage of healthy animals is notoriously low in such “purebreds”. But, this is supposedly the very thing that “drives” evolution. Isolated populations like Darwin’s examples from the Galapagos Isles and such can tax adaptive abilities and showcase what it can do. But, if those kinds of changes are some of the best examples of adaptive change they aren’t very impressive. So, I wouldn’t place too much confidence in adaptation doing much at all in much less extreme, should I say, “typical” conditions.
Information doesn’t just happen and it takes LOTS of information encoding into DNA or RNA to make living things work. Evolution without intelligent guidance, or “intelligent design” requires that all living things MUST have been designed (their DNA encoded) by random or spontaneous events (AKA accidental mutations) This is the fiercely protected dogma of the scientific establishment currently.
But, a problem arises when you try to say that “evolution” cannot depend on any form of intelligence in any way. In computers, it’s no accident that programmers (those that write the code) also have higher IQ’s then the general population. But, somehow in biology, we are expected to believe that the opposite is true. Why is this so? Because, if you connect intelligence in any way with the code in living things, you no longer NEED evolution to explain it all.
Evolution attempts to give a Creator-less world-view credibility. But, evolution pushes simple adaptation to write the most complex and effective codes known without any source of intelligence whatsoever. To deny intelligent design is to deny the code in place in all living things. To accept intelligent design in nature in any way is to render evolution impotent. Evolution reverts back to simple adaptation and mutants remain mutants, better that they stay out of the mix.