A dedicated EVSE is recommended in countries with a nominal 230v mains voltage as they offer improved safety, higher power levels and improved control.
A UK “13A” socket is only rated for 10A continuously which gives around 2.2kW. Whereas a single phase EVSE will do 7.7kW. If you have 6hrs of off-peak electricity that’s 13.2kWh vs 46.2kWh.
A standard socket is fine for the occasional top up or if you cannot install an EVSE, but it is severely limiting unless you are charging every day.