It was. If I was to name Palace's five best players, none of them were on the pitch (for various reasons, 3 of them rested, 2 of them injured).
Henderson; Clyne Holding Richards Mitchell; Rak-Sakyi Doucoure Riedewald; Ayew Mateta Schlupp
That's a depressing team. They did not have their two center halves (Guehi and Andersen), and none of their primary front three (Eze, Olise and Edouard), and also rested possibly their best midfielder Hughes, and had Lerma unavailable (admittedly they don't seem to even have any truly good midfielders). I don't know how anyone can have a look at the team they fielded and think it was a strong one.
I think Mitchell and Doucoure normally are the only ones who make it into their strongest 11 which would look like:
Johnstone; Ward Andersen Guehi Mitchell; Doucoure Hughes Lerma; Eze Edouard Olise
Could be that one of the midfielders that started would be ahead of Lerma though, not entirely sure. Either way that team included 2 or 3 of their best XI, and none of their best best players.