I believe in the 3rd the crowd finally started a Defense chant, and it was actually cool to hear a genuine unprompted chant from the fans. A play or two later they start cheering LETS GO RAPTORS.
However, the next time they tried a DE-FENSE chant there were two crowds you could hear as they couldn’t sync up their timing. DE-FEN(DE)SE(FENSE!), even the next LGR chant felt more muted and weak after that mistiming
So I guess I get why they pipe in the arena prompts and it seems they decided to start doing it in the 4th. It helps the crowd (who now want to cheer) be able to do it in sync
There was definitely much less area music and sounds coming through the PA. I assumed they were working out the kinks as it was game 1.