I didn't realise you were actually asking, the third person usage threw me off
For Christians with a high view of Scripture (e.g. that the theological and ethical principles governing what was written in the Bible are prescriptive for us), there seems to be sufficient Biblical witness against drunkenness (Eph 5, Gal 5, etc).
I think we can see some of the rationale as well though. For one, I think Scripture has
some normative ethical call for us even when we don't think there's anything wrong with an act in itself. It might be, for example, that God calls us to some ritual acts or behaviours which have no moral value in themselves, but have moral value because God calls us to them specifically in order to allow us to be marked out as separate, and to refine our dedication to him. This seems to be the basis for much of Leviticus, for example. As well as being personally helpful for us in that respect, it also marks us as different for other people, and so can be incredibly useful in an age where there's such mixing of Christianity/ideology/politics etc, not least for providing opportunities for evangelism. Now, whilst many of this is superseded or made redundant in new contexts (i.e. we do not have the same vocation as the Israelites in following Leviticus), it certainly seems that there is a place for some of these ethical commands, particularly when they are also present in the New Testament. So even if we did not see drunkenness as morally wrong intuitively, I think we have good reason to refrain from it on this basis. It allows us to remain separate, which is useful relationally, as well as in virtue (discipline in transforming our character and all that; cf. Tom Wright, Virtue Reborn), and in evangelism.
But, on top of this, I think we
do have good reason to also think that sobriety is important on other scriptural bases. As well as the specific injunctions against it and opportunity for evangelism and holiness sobriety provides, we are also called to both take care of our bodies, not just because they are Temples of the Holy Spirit but also because, particularly in a country with a welfare-state healthcare system, our long term health has enormous implications for the systems which other people contribute financially towards, as well as for our understanding of economical stewardship and responsibility in allocating resources. Furthermore, we are called to have our minds and bodies oriented towards God, as well as to take proper responsibility and exercise wise stewardship over the capacities God has given us in the short term, too. I'm not sure how well alcohol, as a general suppressant of the nervous system, contributes towards us using our minds, bodies, and intellect all for the glory of God, and it may even do an injustice to those who weren't born with these capacities.
It is a question both of resources, and of witness. If we are spending a considerable amount of money on damaging our body and mind in both the short term and long term for a temporary kick, and at the same time participating in a culture which, although not necessarily always wrong, is certainly heading towards alcohol pleasure-dependence (which is perhaps even more significant socially and theologically than the clinical disorders associated with it, and should really have been the main criticism in all this. In fact, see [1]), then I'm personally not convinced it's the most wise stewardship and culturally-subversive living that we are supposed to be achieving. It simply doesn't strike me as particularly radical living.
Just my two cents.
[1] It just doesn't seem to me as if someone who goes out and gets drunk can speak prophetically with real life, clarity, and effectiveness into a culture so absorbed with and dependent on alcohol rather than God, and one in which alcohol has caused so much strain on relationships, finances, and so many difficulties with God. Sometimes a different kind of morality based on circumstance is required, as I argued in the opening paragraphs. Small problems where something is abused on a minor scale (e.g. science) can still be used, and a proper use demonstrated for them. But when there is a society so captivated and broken by something, I think it takes much more revolutionarily subversive living to speak real life into those communities.
Edit: Yes, I do realise how suicidal this is on a largely liberal forum such as this. Honesty must come ahead of +rep here, I'm afraid