Have you looked at individual defenders of teams that finished above Arsenal last season? I think Laca has improved but you are certainly right about him.
I mean I don't think even the club see Holding as first choice. I think he's just played a lot this season cos Luiz has played less for whatever reason and the whole Saliba situation. But yeah Lacazette is ostensibly our first choice no. 9 and is just nowhere near the level we need, he was maybe at that level for one season but that's it. Desperately need an upgrade there.