Well it might not be your government that institutes this idea. Given this is a bank in the UK you or I might not be allowed to vote on this type of thing, but if general populous begins to see the choice of technical decisions are more in the hands of the professionals and not so much the company it could very well change. And it might be companies that push legislation like this if they feel they don't want to bear the legal risk.

Now usually there is professional insurance that consulting companies have to purchase for liabilities just like this. If you are consulting firm implementing systems for banks they will require you carry $2 millions/dev of insurance should there be a screw up like this.

Maybe this is the best option because I'm not exactly behind supporting measures to certify or regulate our industry, but I fear bad behavior like this might force it. This is a hack rookie mistake. I'm fully aware of the ramifications of doing something like this, but I'm not immune to mistakes that could result in the same damage. However, a law like this would treat me the same way as these hacks.