Any fool can/could…
Definition 1 of 1
Pro Tip 1/3Ease emphasis
Use the phrase to stress that something is very easy or obvious, even for someone with no expertise. 
Any fool could operate this machine; it's so simple.
Pro Tip 2/3Sarcasm tool
The phrase might carry a tone of sarcasm, implying the other party is missing something obvious. 
Any fool can see that won't work. Why can't you?
Pro Tip 3/3Understatement
Sometimes used to understate the intelligence required, suggesting the task is simpler than it appears. 
Any fool could learn these rules, but mastering them is another story.