No. We as a nation have gotten very dumb. Here is an 8th grade test from rural Kansas in 1895. No one here, including me, would be able to pass it.
The problem is Grammar and Orthography is completely made up, they are arbitrary. Noam Chomsky has written extensively about language, the human brain is incapable of not developing a language and a form of communication. Kids are a sponge when they are young. If all languages disappeared tomorrow, you'd have all new languages popping up all over the place among different cultures fairly quickly and they would eventually establish standards and make up rules for you to memorize.
There's been a lot of debate whether grammar and spelling are even important, one could be impeccable in these areas and have nothing interesting to state. However someone like Richard Feynman the famous physicists that helped on the Manhattan project regularly spelled words wrong and when asked he stated because he didn't care.
These kids didn't have Google back in the day. They flexed their brains in different ways 100+ years ago, mostly through memorizing.
If you go back 2000 years there where those that memorized vast amounts of text and could recite them. Homer's writings, 10,000 pages of Buddhist Pali Scriptures, the Vedas. It's pretty astonishing what a person can memorize without error.
The problem is it doesn't teach you to think critically. I'd rather have a kid that was immersed in philosophy and math, that way he can figure out just about anything that comes in front of him.
As for the 1895 test, these kids didn't just have these questions out of the blue, they studied these topics, they were prepared for the test. I had to do a lot of memorization myself in school, especially in college, it was ridiculous where we were handed 500 pages of printouts you were expected to memorize more or less by the end of the semester, this is fine as I needed this knowledge to pass exams.
I don't think kids are dumber today, I think the school system is little more than a baby sitter and even the so called gifted classes aren't exposing students to anything other than preparing for standardized tests for higher placement.
If a kid from China took the 1895 test he wouldn't be able to answer any of the questions. Someone from Japan the same.
What can I do with the knowledge from the 1895 test. Nothing. You have a head filled with some rules and some knowledge that won't do anything for you at all.
Now don't get me wrong, I met a lot of Grammar bitches from previous generations, women that were obsessed with every rule of writing. They memorized those arbitrary rules and damn-it you were gonna obey them or you were a dumb ass. So when they'd do that I'd write out a differential equation and tell them to solve it, that shut them up.