Your use of scare quotes is appropriate, because there is a qualitative difference between intelligently-driven and unintelligent attacks. Not to mention the intelligently-driven attacks when the attackers are manifestly more intelligent and skilled than the defenders! If computer security experts didn't have to worry about intelligent attackers, computer security would be very nearly a solved problem.
WRT the house analogy, it's easy to extend that to "intelligent" attackers: intruders of any kind, e.g. robbers, animals, etc. Many install security cams, in my city (Istanbul) many condos have railings that protect the windows of the lower flats, we have locks on doors, alarms, barbed wires, safes, body guards, guard dogs etc., all to stop the intelligent attackers to actually using their intelligence. What's analogous in programming is using the best practices available, and the use thereof must be imposed on any critical systems (e.g. banks, medical institutions, communications tools [e.g. social media] etc.) by the governing bodies.
While true that accounts for a large amount of the problem, probably the clear majority, computer security would remain a problem even if developers were uniformly highly competent. Competent use of existing crypto systems, which are broken three or four years later, would still be a problem. Meltdown and spectre would still be a problem. Building a safe execution sandbox is legitimately difficult.
But it would be a qualitatively different world than the one we live in.
Certification solutions to the software problem generally face the problem that it is very difficult to imagine any scenario other than one in which people grotesquely incompetent to write the certification rules are the ones writing them. We do not, for instance, want our certification authority to sit there and mandate waterfall design processes, which I would consider at least a 25%-probable outcome, and that's awfully large for something as catastrophic as that would be.
"WRT the house analogy, it's easy to extend that to "intelligent" attackers: intruders of any kind, e.g. robbers, animals, etc."
No, houses are never under such intelligent attack. Even when attacked by humans, they are not attacked by ninja stealth thieves who go in, photocopy your SS card, and get out again without leaving a trace or something that sounds absurd to even use as an example. There's no physical equivalent to breaking into millions of houses at a time and making off with such data. They're attacked by people who smash through the physical security. Anybody can do it. "Anybody" is who does it... above-average IQ people are not generally breaking into houses. (Above-average IQ criminals find much more lucrative and safe criminal hobbies.) Not just anybody can put a tap on a fiber optic line, feed it to a high speed data center, and process it in real time to extract out terrorism threat info, or even just exploit an XSS vulnerability on a website.
