There's a bit of absolutism in the answers.
The reason for potting things varies. If it's to keep fragile connections and wires from breaking, it can work perfectly for that, for many years.
No it's not suitable. Won't last a year or two before starting coming off. In outdoor conditions will fail to protect during first winter.
Is there something that happens at low temp?
For hundreds of thousands of years, humans used simple resources like tar, beeswax, and sap/rosins for reliably connecting and binding things, well before bone and fish glues were invented. These early glues have some similarities with hot glue. One of the most obvious ways to make hot glue more durable is to add fiber to it to help bind it together. To keep a joint adhered, one can keep pressure on the connection (by wrapping/binding with perhaps fibers+glue where possible). It is also sometimes possible, if/where it eventually fails by loss of adhesion, to use PVA glue (Elmers or wood glue) to glue the perfectly shaped hot glue interface back together.
A couple ways I use hot glue for electronics:
Small proto circuitry. So if I were to need a small circuit with say a few wires going in, and a few wires going out, I might take a thin piece of lamination (like thin FR-4 or even single-sided copper clad) and cut out 2 pieces that are large enough to totally cover the entire protoboard circuit. Shape them the way I want and route the wires how I want. Then cover the entire circuit in hot glue and slap the laminations over it on either side until glue oozes out the seams. Trim as needed.
Strain relief and waterproofing of a cable going into a plastic/metal housing. What I will do is wrap a cord/string around the cable while adding hot glue. The string is under tension, so it absolutely can't slip over the cable sheathing. The hot glue glues the string to itself, so it absolutely can't lose tension. Once you have your bulge on the one side, the wire can't pull out. Glue it to the housing, then cord wrap the other side with more string and glue and a good glob of glue. Once this is on, it is not coming off without time and tools and directed deconstruction.