It's hard not to read the quote you give as basically admitting that they _can't_ entertain the idea that there are "wider security implications" because that would be tacitly admitting that the language itself is built on shaky foundations. Something being a "core feature" _increases_ the scope of any security implications, but it also makes it a lot harder to fix without having to change fundamental parts of the language, and it sounds like that would be a non-starter for them.