To be fair, most on this forum have agreed that the likes of Richarlison and Gomes have been, as you say, “decent additions”.Unsurprisingly, it must be 'turn against all our players and say they're awful time'. When will it be perfectly acceptable again to say they're a decent addition?
But to answer your question directly, I for one would agree that new defenders were decent additions if they improve our defence.
Being at fault for goals or generally lacking the savvy to deal with the general threat in a defence that leaks six goals at home, is not what I would consider an improvement.