It might be appropriate to spend a lot on education, if there were a benefit! But as you can see in the first chart, its not at all obvious that all this increased spending has had any measurable positive effect.
I also find there are benefits to spending (on my) education. But if we can't show benefit for a specific kind of public spending, is it justified to take other's money and spend it on "education" in a way which has no measurable impact? I don't think so.
It might be appropriate to spend a lot on education, if there were a benefit! But as you can see in the first chart, its not at all obvious that all this increased spending has had any measurable positive effect.