No, it is not meant in a pejorative sense.
Journalists report on events as they occur. It is always helpful to get additional input from parties involved, e.g. family, employer, public relations representative, attorney, or experts. Sometimes that isn't possible, because the event just occurred, and has been confirmed by authorities. If the event or situation is newsworthy, journalists must report on it, rather than waiting until they get a response from whomever they contacted for additional information.
These are not "weasel words". In fact, good news media reports often republish the story with one or more updates, as responses to comment requests are received. Reuters is particularly good about doing that, occasionally multiple times for a news story! Both Thomson Reuters and the BBC have guidelines on requests for comment.
Via Reuters Handbook of Journalism excerpt, "Vetting"
Give the other side every opportunity to comment. If you don’t elicit
a comment in an initial contact, call again. Record all the times you
tried to contact them. If they decline to comment, note that down.
and excerpt, "Legal":
When a key subject, company or institution declines to comment,
provide its point of view. Preferably, this would come from a
credible, on-the-record source; at the very least, provide contextual
information that may put things in a more neutral light.
Via BBC Editorial Guidelines - Right of Reply excerpt:
Providing a fair opportunity to reply to allegations requires
providing enough time to make a response. The amount of time that is
fair will change according to circumstances, including... whether
there is a pressing need to broadcast in the public interest; the
nature of the subject and their resources...a large corporation with a
sizable PR operation may be expected to respond quicker than a small
business with just a few employees or an individual.