It’s actually a semi-reasonable effort by the NHS to get some flow efficiency into the GP practice.
It means that if you are in a more urgent need you can get a same day appointment, but if you require a general appointment for a non-urgent issue you have to wait.
2 weeks isn’t even that long. I think it’s a good system, imho.
If you’re in an urgent situation, NHS 111 is a fantastic service that will get you to a GP within hours (In my experience, we were told we need (emphasis theirs) a GP within 6 hours, and this was at about 5:30pm. They got us an appointment at 8pm.). This would not be possible if GPs book out all their slots possible.
It’s not perfect, but it’s an alright system when you are desperate, and it’s great to see flow efficiency recognised in an organisation like the NHS.