It's not enough to make a non-zero profit. You have to be as profitable as similarly risky industries, or else capital will flow to those industries instead. Drug development is similar to tech in many respects--a lot of the work is done by startups (which are later acquired by the big companies). If profits go down, the money for acquisitions goes down, and the incentives to form and invest in the startups goes down. Instead, the capital goes elsewhere.

If the government decided that Internet tech companies were "obscenely profitable" and started regulated prices so profits went down to 10% (instead of 30%+ for some companies like Facebook), do you think Silicon Valley would still produce the same output?