It started with an underwhelming crowd, which only matters because of how he’s hyped and exaggerated expectations for them.
To paraphrase the movie Spinal Tap, Trump’s popularity isn't waning, his appeal is just becoming more selective.
But even the crowd who did show up seemed to be more subdued than normal. Sure, they applauded. Sure, they cheered. But it seemed like they were going through the motions. There’s a difference between a crowd that is enthralled and one that is polite. This was a polite crowd (which is something you don’t often say about the MAGA crowd).