Question about Digitec GaN 3-Port Fast Charger

At full power, the device can get quite hot, which is normal and to be expected with this power density. I have also observed the same with other power supply units, some of which get even hotter. So there is no cause for concern.

The fact that the electrolytic capacitors in the device would prefer it to be cooler is another topic...
The suggestion from @svcurcio to choose a charger with a little reserve upwards so that it doesn't have to run regularly at maximum is definitely a good idea.

My device also heats up to around 45°, which I consider normal for this size.

Although the charger can deliver 65W, this is relatively high for such a small device without ventilation and heat sink.
The temperature is therefore normal. I would use a more powerful charger for a notebook.