It depends honestly. Here in the states, we GFCI kitchens, bathrooms, laundries, garages, crawl spaces underneath houses, and exteriors, basically anywhere it could be reasonably expected to come in contact with water or an unexpected grounding/earth source. From there, you can either do a GFCI breaker or receptacle. Both will protect everything downstream from the device, but the choice comes down to convenience of operation. I’ll generally do GFCI breakers for dishwasher, disposals, refrigerators, etc, just so that if the GFCI trips you can reset it in the panel so you don’t have to pull the equipment out to get to it, but I’ll do kitchen and bathroom counter convenience plugs as a GFCI receptacle (and daisychain all downstream kitchen receptacles from the GFCI receptacle) to be able to reset it right there at the point of use.
You could in theory GFCI protect an entire house/flat, but it likely comes down to cost saving and avoiding nuisance trips. Motors as they age tend to leak current and trip GFCIs, and any number of delicate electronics can be finicky, so that’s typically why we only use them in wet locations.
It really is to save those that aren’t smarter than your average Bear from themselves. Logic would dictate that, yes, keep electronics or electrical appliances away from water, but too many people don’t connect the dots. Also too, accidents happen to the best of us.