Yes, this is not uncommon in US politics.

Here’s what Wikipedia has to say about it:

In U.S. politics, the period between (presidential and congressional) elections in November and the inauguration of officials early in the following year is commonly called the “lame-duck period”.

A president elected to a second term is sometimes seen as a lame duck from early in the second term, since term limits prevent them from contesting re-election four years later. However, not personally having to face the electorate again makes a second-term president more powerful than they were in their first term as they are thus freer to take politically unpopular actions. However, this comes with caveats; as the de facto leader of their political party, the president’s actions affect how the party performs in the midterm elections two years into the second term, and, to some extent, the success of that party’s nominee in the next presidential election four years in the future. For these reasons, it can be argued that a president in their second term is not a lame duck at all.

So while you’re right that the assertion the author is making is misguided, it’s a fallacy that is made often enough that some might conflate it with reality.