Yeah, point totals down leaguewide and playing for a team with a bad defense and little offensive depth and no good left wings. It's all inevitable decline though.
There's a bit of everything in there. One, they didn't have a real secondary threat to pull the other team's defensive assignments. That should change with the addition of Patrick and the growth of Konecny. Another, he spends like 75% of his time with Voracek, who is himself not much of a shooter. The two of them have had Raffl, Weal, and whatever repurposed right wing on their left for a couple years. That should change with the addition of Lindblom. Also a garbage defense behind them that got pinned in its own zone constantly. That should change with the addition of Sanheim and the continued growth of Provorov and Ghost.
Certainly, Giroux hasn't played with the same confidence he was a few years ago. He was extremely quick-thinking and electrifying at his best. He seems to not make the snap decisions anymore, thinks too long, passes when he should shoot or shoots when he should pass. But that's mental, and that can come back as the team improves. He's been slowed down a bit by injuries, and though he used to produce some offense with speed it was never the main driver of his greatness.
Sure, he's not going to put 85-90 up regularly again, but who is? All these people hammering away "YOU CAN'T DENY THE NUMBERS ARE GOIN DOWN!!1!1" right, but you should always put context with numbers. There is no reason the Flyers would trade him: he'll be a great anchor on an improving team. As the team ascends around him, his point totals will improve.