I'd really encourage you to watch some football games around the league. A huge part of the change is defenses doing a fantastic job. They're all playing shell coverages now to eliminate big plays and many teams are rotating coverages after the snap to muddy the reads. They're some great QB play, they're just not having as much explosives.
And defenses are defending the run with light boxes and there's an increase in simulated pressures across the league all contributing to making it harder on offenses. Not only that, defenses have really clamped down on RPOs since like 2019.