Geez, your government sounds like a lot of fun. What do they think? “Well, today, instead of getting rid of radical muslims in our midst, we’ll just micromanage homeowners and force them to use professionals who donated big-time to our parliamentary campaigns!”
It is more of typical left bureaucracy and we are looking out for you nanny state which in reality in most cases has not made the work any safer or better.
In theory I suppose it is better to get a registered gas fitter to rig up a cooker or gas fire or connect electrics to the main supply or major electrical or professional builder/engineer do or oversee major building work which is what they are basically saying but now not only do you have to get this done but prove it when you sell your house otherwise you will need to get a full safety survey done at your costs not the buyer's cost.
Basically it comes down to the government wanting to regulate and in their mind make sure you are not selling a property with either substandard or unsafe gas/electrics/structure etc., instead of trusting that home owners would do that. I suppose again we all suffer for the few that flout the rules. I believe there maybe some get our clauses such age of property, number of bedrooms etc but eventually I suspect all houses will come under the rule and if you have not had any major work done recently then you will have to get a survey of the various services and structures done.