Thankfully the Geneva Convention doesn't agree with your faulty logic. Your personal value judgements on the quality of journalism being produced has absolutely zero bearing on whether killing a journalist is acceptable.
A good write-up here.
Just to check if you're applying your "logic" evenly or just cherry-picking where and how you apply it: should targeting of Russian medics be allowed, since they're only saving the lives of Russian soldiers? If not, how is targeting a journalist (for Russia) different than targeting a medic (for Russia)?
And remember: the Geneva Convention disagrees with you. Maybe that should be motivation to check if what you're saying is actually reasonable or not.