The most convincing argument against the mistakes being intentional is that it would be self-sabotage. Even if you believe there is a vast media conspiracy to damage Trump, what good does it do media outlets to plant bogus stories that are momentarily tantalizing, but quickly and easily disproven, that they then have to apologize for? It hurts their own credibility, and far from hurting Trump, it adds fuel to his bullshit bonfire that all news is fake and you can’t trust anything the lying media says. If it is intentional, either the reporters and editors involved are complete fucking morons or they’re actually agents provocateurs trying to help Trump.
Spreading horseshit far and wide is a useful tactic if your goal is ephemeral— say, to sway an upcoming election. In a long and arduous legal investigation or political process like impeachment, where Joe Sixpack is not directly involved and there’s heavy and highly organized opposition, not so much.