Is this yet another example of religion bending to fit with science?
No because the original statement and the new one don't conflict with each other. But it might be bending to bad apologetics if such a change were to actually be incorporated into an official work such as the Introduction in the LDS edition because such is not necessary. Although LDS doctrine is open to revisions of canon and doctrine (though no one can point to a single revision that had any truly consequential effect), it is unwise imho to effect unnecesary changes.
There is a larger issue going on here and that is the definition of canon and doctrine which many of my fellow LDS can't quite seem to pin down and it is well illustrated by this principal ancestor issue.
In the thread in question, I am arguing that all the extra items added starting in 1981 are canon. Notice that the arguments against such a notion I get in response range from "I don't believe it." to quoting to opinions of a FARMS and a BYU scholar. I have nothing against these wonderful organizations but my arguments for such a notion come from a more authoritative source, the Church itself and how it packages and presents it's canon.
Now there is no way in heck you can convince me that the 'helps' (as they put it) are not official doctrine because of official statements about what doctrine is. But there is plenty of room to wiggle on the issue of canon (except for the JST excerpts which must be canon because the Church claims they restore doctrines to existing canon) because notwithstanding the fact that my arguments come from a more authoritative source, they are still quite weak.
So, what is the point I am trying to illustrate by arguing this way? Can you guess?
One can certainly accuse me of trying steadying the ark, but aren't those other LDS who call for/wish for a change or modification of 'principal ancestors' also guilty of the same?