From my understanding, it's the type of meddling that's vastly different.
The "meddler proof" in regards to Biden relates to electoral fraud in specific false votes, dead votes and the like. Mail in ballots not being fake, recounts actually being valid, etc.
The "Russian meddling" query relates to social media manipulation, email hacking and revealing/faking scandals to cause people to react and vote for someone else. You can report what people are talking about without saying that what they are talking about is false or fact. Then people see it on their news feeds, hear reporters discussing it, and automatically it gets shifted into the mental box of "its a true thing because people are talking about it."
If you use Facebook algorithms to keep feeding specific stories to social groups you can affect the way they behave.
So I wouldn't classify it as direct hypocrisy there.
Still, onto other things...