The problem is, the 3Rs are currently underpinning the education system, yet as you have identified we already have people who can't add up or spell. I'm sure the majority have reading difficulty as well.
The 3Rs have already failed.
I also have to agree with Stuart on this.
The 3R's are essential.
To reply to your quote, the 3R's have not failed but the teaching has.
To be fair this is often because of how the subjects are prescribed to be taught.
You need a basic set of skills that do not rely on 'machines' to cover for your 'Blind spots'.
How do you use the 'machines' if you cannot do the 'basic math', as the Americans would say, in your head.
I have seen people use the 'machines' to get the wrong answer because they have no way of knowing the roughly 'right' answer.
As my teachers used to say, "calculators are just a quicker way of getting the wrong answer if you do not know the basic techniques".
Yes you are true, the reading skills are getting worse as well.
Just witness the usual mayhem on forums when people misread/misunderstand an extended argument because they cannot comprehend anything longer than a tweet.
Not to mention the TL;DR mentality.
Not all statements can be made briefly, without losing the fine nuances & important facts of the argument.
Simplification *can* change what you say and make your argument invalid by dint of omission.
Language is being changed by these attitudes and the ability to communicate is being dumbed down.
This is not just my opinion but is actively being monitored by many groups.
i.e. OED has to now include txt speak and other contractions of language.
[Yet another Hobby Horse ..... I will need a bigger stable soon
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