I actually had a very similar conversation with my wife last night about our son's future education (wish me luck) where I effectively said the same thing.
To paraphrase my argument: reading, writing and math are too important to be taught at school or rely upon their standardised tests. if I have to wait for a test result from school to tell me my child can't do the thing, I've already failed. And in addition he'll have started on music, some sports, sciences and programming likely before he ever reaches a compulsory classroom.
This idea that teachers, in a group environment, with a standardised curricula can compete with that is just downright dishonest. And the idea that this is meritocratic and that children compete on some level playing field is absurd. You can't teach finance and programming and economics well at school because most current teachers do not understand or cannot implement such into their own lives,and philosophy just isn't taught in general.
By the time you reach cs 101 at university, how is the average child who learnt to type at school and that computing is an iPad with YouTube attached supposed to be realistically competing with the other students who already have 10 to 15 years of experience?
and if you cannot read or do math at 8, on average, what sort of life have you had and how do you compare with children already thriving and building upon what they know?
perhaps we also have a disagreement about where lower/middle skill jobs and wages are also going? you might be assuming "well, he won't thrive in comparison, but he can live a nice normal life at a "insert basic job here", under the assumption basic job will exist or have a good living standard.
By all means, I want a world where learning is available to all and we tell people that they can improve, but I'm not in denial about the stark probabilistic realities a lot of kids face, and I haven't even touched upon anti-intellectual attitudes and active consumerist/marketing/ ideological strategies that are actively trying to stop people learning to be educated or think critically...