This is the most garbage logic. His approval rating does not directly equate to fulfilling promises. There can be cause and effect, but it's not guaranteed especially when there's so many factors that impact approval rating.
Presidents get a post election bump. It has nothing to do with fuffiling policy promises. Hell, the bump began before he took office, so obviously it has little to do with him fulfilling promises. Trump had a bump his first term too. But guess what. Literally every other president, including Biden, had a better overall approval rating at the beginning of a term than trump ever has. Time will tell where his approval lands.
I didn't say it wasn't even and imperfect metric. I'm saying that its almost no metric. Perhaps even evidence of poor performance to be honest. Because the approval bump is a repeatable and measurable phenomenon we observe after every election that has 0 to do with presidential policy or action. And his post election approval bump is the second worst in history, only below his own poor approval bump from his first term.
Information is relative to the environment and circumstances. Is doesn't exist in a vacuum.