You're arguing nonsense, the politifact article doesn't say the video's definition is wrong. It says the poster of the video "glosses over" the term 'generally' which they do. Your whole argument as to their thought process as to which second in the video they flagged (while ridiculous) is easily explained by this fact.
> To me, that’s a clear indication the definition is an important part of the reason for flagging.
The article is also titled 'No, the White House didn’t change the definition of “recession”' To me, that's a clear indication of what the most important (and valid) reason for flagging was.
> The video in question uses a different (dictionary) definition of the term from the authors of the article.
Both the video and authors of the article use the same definition. The article notes that the video "includes an important word that the narrator glosses over" (hint its the word 'generally').
> This is partly the justification for them declaring the video as false
Using a different definition is not their justification (partly because you just made this connection up). They ruled the post as false because it stated the White House was changing the definition of 'recession' when it was not.
> flagging it as potentially harmful misinformation.
The intent of the video is clearly to indicate the White House is changing definitions to suit their narrative. In reality this was not the case. The effect is discrediting or undermining the trust in the white house. If you think this isn't potentially harmful, that might speak more to your political inclinations than the objective reality.
> The overreaction alone is sufficient for me to question the website’s priorities.
First 5 seconds of the video: "So the White House is now trying to protect Joe Biden by changing the definition of the word recession"
Content of the video: Uses siri's definition which states a recession is "...generally identified by a fall in GDP in two successive quarters." The poster ignores the 'generally' when comparing to the White House website which states that the two quarter definition is not official. Followed by a rap battle meme.
Obvious intent of video: Paints a narrative that the white house is changing definitions of words to fit their needs.
Title of the politifact article: "No, the White House didn’t change the definition of “recession” "
Content of the politifact article: The white house didn't change the definition of recession.
Reality: The White House didn't change the definition of recession.
If anything this viewpoint is unreasonable and forms the basis of an informal fallacy, among the lines of a false equivalence. You are claiming an equivalent outcome based on an oversimplification to one factor ("all politicians lie the same") and/or ignorance of the plethora of factors that separate (and yes, in some cases confound) both parties.
I know plenty of Republicans who think Democrats lie more and I know plenty of Democrats who think Republicans lie more. But I wouldn't justify a false compromise through anecdotal evidence.
> To me, that’s a clear indication the definition is an important part of the reason for flagging.
The article is also titled 'No, the White House didn’t change the definition of “recession”' To me, that's a clear indication of what the most important (and valid) reason for flagging was.