The Washington Post published an opinion piece two days ago calling for using "widely" more narrowly, particularly in such usages as "it is widely believed that..." or "it is widely suspected that..."
The author, Barton Swaim, concedes that sometimes such a statement is simple, justified, and unremarkable. But not always...
'Just as often, though, that little word “widely” seems designed to appear to do the work of citation or argument without actually doing it. '
You do see this sort of usage in the "best" of journalistic sources, such as the NY Times, which does a lot of real reporting, but also a lot of very vague sourcing.
When reporters write "widely believed"
Readers are right to feel vaguely aggrieved.
If belief is really widespread,
How hard can it be to name some sources instead?