Again, I think, citation needed, since conservative media does like to bang on about this a lot, but I’ve not seen actual proof that education standards are falling, or worse than they were when I was at school.
What I think has happened since the close of grammar schools is that the gap between most educated and least educated has closed significantly. This government report from 2023 shows that gap closing, while also showing an improvement from previous years.
https://assets.publishing.service.gov.uk/media/675330e020bcf...