John Birt was the Director-General of the BBC from 1992 to 2000, which made him the incumbent Director-General when the Paul McGann tele-movie was commissioned, produced and broadcast.
However, his most direct influence on Doctor Who was probably his interest in developing online content. His efforts in this field led to the start of BBC On-line — as it was then styled — and, in 1999, the Doctor Who website. (DOC: Interweb of Fear)