Earlier quoted context omitted.
The point isn't that we need to know who came up with what, it's that we need to know the justification for their assertion. If it becomes common knowledge that "the Republican party lost their way after 2000", people will stop backing up the statement. As time goes on, nobody will know why "Republicans lost their way after 2000". In the future, careful historians will want to know who first made the assertion so tha…
I get it--as it gets impossible to find out who came up with what, content creators are an indirect casualty but historians are a direct one because that's their actual job! That's sort of funny. I guess they'll have to use fancy statistical analysis like everyone else now.
A big part of history has always been gathering and interpreting sources, to figure out the validity of assertions like that (whether contemporary or retroactive). Hearsay and speculation are nothing new. As the article notes, history isn't about reciting names and dates, it's about making a case to support or refute an interpretation of what happened, based on available evidence.