I think the onside kick was a bad call and Campbell does deserve some level of criticism for it. That said, there were many other things that ranked higher on the list of reasons why they lost than the decision to onsides it. Notable an inability to contain Jalen Hurts, contain AJ Brown, and allow plays to develop because they weren't getting any pass rush. On offense, Goff's rough first half and the dropped passes out rank the decision to onsides it.
Was it the right decision to take an onside kick there? No. Did it hurt them and allow for the Eagles to have an easier time scoring a TD. Yes, probably. I don't believe though that it cost them the came and they would have one were it not for that.