No it isn't. Yes people can be intelligent and rational but also unintelligent and irrational. Further, the target audience of popular science writing very often don't have the necessary training or knowledge to distinguish claims that are well supported from those that aren't.
What is given in those publications is well supported. The only place you'll find something else is in junk science sources. For common texts and reputable publications, the inclusion of such terms as "may be", or "maybe wrong" for well supported and held results and theory is unwarranted and only serves the interests of those desiring to push nonscientific claims in contradiction to the real science presented.