As has been mentioned, then using quality components where the electrical parts is actual copper with a corrode protective metal coating (nikkel, chrome, tin or the like) - is a very good idea. As this will lower the resistance and the possible heat buildup in the sockets/connectors.
Using Blue Sea Systems 12V sockets, plugs (and more), will ensure that the optimal metal (copper) and optimal thickness of copper is being used in the product.
Blue Sea Systems 12V sockets and plugs also has a locking mechanism included in the design.
This locking design is a good idea, as it ensures a dependable and low-heat-connection between socket and plug.
The cheap 12V sockets/connectors are otherwise notorious for easily coming a little loose, resulting in poor connection, that might lead to unexpected heat-up in the connection.
This heat issue increase the more power that is drawn from the 12V sockets. Typical if more than 4-5 amp (48-60 W) is handled by the 12V socket/connection.
A quality 12V socket/plug, with a locking-secure-connection, can otherwise be expected to stay acceptably cool, up to 10-15 ampere (120-180W).
Power loss happens in wires and/or connectors, if the core is not copper, but some other metal.
Power loss also happens if the wire is too thin (or too long) for the actual ampere load.
Or if the thickness of the copper in the socket/plug is too thin, for the actual ampere load.
Or if there is corrosion on the metals in the socket/plug. Hence the advantage of anti-corrosion coating on the copper plates of the socket/plug.
According to some charts, it is considered okay to use 20 awg wire with 10 amp fuses. And 18 awg wire with 15 amp fuses.
Like this fine chart
https://www.powerstream.com/Wire_Size.htm
But thicker wires are always safer, so I like to use 16 awg wires for 12V sockets. No matter if they get protected by 10 amp or 15 amp fuses.
And If I am running 12V wires from one end of a vehicle, to the other end of the vehicle, and there is a 15 amp fuse to protect the wire, then I prefer to use 10 or 9 awg wires. As thicker wires results in less voltage loss for longer runs. Like longer than 5-10 feet.
But if you do not expect to load 15 amp on a long wire (over 10 feet long) it is absolutely not necessary to use such thick wires.
I like to do 30-50% better than the chart, on permanently mounted wires.
If you expect to be able to fully load each of your 12V sockets, then each socket should have its own fuse and wire, directly from the battery, to the socket. And the fuse should be placed close to the battery.
The easy way to do this, is to use a fuse block. And place the fuse block, close to the battery.
Individual fuse-holders works just as well, but can get a bit more messy if you end up using more than just a few wires connected directly to the battery.
With a fuse block, there is typically a high amp fuse (30-50 amp), for the connection going directly to the battery, and then for each distribution connector from the fuse block, it is possible to use a 2-15 amp fuse for each individual wire leaving the fuse block.
Remember to use a suitable thickness wire from the battery to the fuse block. The thickness of a wire should always match the size of the fuse. As fuses are used to protect wires (and connectors) from over heating.
This may all sound a bit much.
And it IS possible to do a simple solution like one of these units:
https://www.amazon.com/Linkstyle-Cigarette-3-Socket-Splitter-Voltmeter/dp/B07QHYBRBD
And simply add a 15Amp fuse in front of the unit (place the fuse close to the battery)
But you asked for a safe and good quality solution, and then the Blue Sea Systems components, and a fuse block, is the best way to go.
