As big city newspapers go through financial implosion their older employees retire early and take buyouts. These are replaced by young, bargain basement “reporters” and 10-cents-a-line “contributors.” These “journalists” are highly vulnerable to bribery.
No disagreement on the problem of replacing long-term experienced reporters with young people at lower pay levels. That would have happened to me if I had not resigned voluntarily from a prior newspaper which fired its publisher who had spent his entire adult life with the newspaper company. The new management replaced virtually the entire staff with people who had little if any prior experience and, in a number of cases, minimal education in the field.
However, at the level of the Washington Post, people being hired are likely to be either the very best recent graduates of journalism schools who have interned there or people who have moved up from smaller newspapers. For the Post's people, getting hired is a huge promotion in professional status and likely though not necessarily in pay as well.
I don't see bribery as being a problem for reporters at the national level. At lower levels, maybe, but more likely issues of conflicts of interest and incompetence.
There's more than one way to “bribe” somebody. Money won't work with anybody with any level of ethics, but offering or withdrawing access, friendship, and other information can accomplish the same thing.