It’s easy for us to see their biases today because new perspectives from different ethnicities, feminist theology, Catholicism, and Judaism have now entered the field of biblical criticism and revealed things early scholars overlooked.

[...]

This has changed biblical criticism's central concept from its original profession of ‘neutral judgment’ to that of beginning from a recognition of the various biases the reader brings to the study of the texts—including those early critics.

So?

Then by the end of the 1970s and into the 1990s, "one major study after another, like a series of hammer blows, ... rejected the main claims of the Documentary theory, and the criteria on ... which those claims are grounded."

The Documentary Hypothesis has been making a comeback as of late, though, thanks to the likes of Joel Baden, Jeffrey Stackert, Baruch Schwartz, et al.

Its original form is outdated information that is no longer generally accepted” is the reasonable and valid response.

Whatever other details there may have been, the final Redactor had four sources before him to combine into one written Torah.

As for bias, so what? It's not like a lot of scholars are trying to reconstruct ancient Israelite religion.

It is because of new "liberal" perspectives that there are now theological efforts to recast the written Torah as the true first rabbinic book, as well as to recast the Yahwist, Elohist, Priestly, and Deuteronomic Schools as "Rabbi J," Rabbi E," "Rabbi P," and "Rabbi D," respectively. There are moments of recorded consensus amongst these competing Torah schools. There are recorded majority opinions. There are recorded minority opinions. These opinions can then be used to reinvent theologically and not just reconstruct.

When applied to modern conduct ("law"), source criticism can be utilized to reaffirm Divine inspiration underlying at least 140 or so commandments (i.e., two or more competing Torah schools in agreement). Source criticism can be utilized to "pick and choose" the remainder by reaffirming or reevaluating Divine inspiration underlying them.