If it's just the connector getting hot and not the cable itself, then it is a high resistance at teh connector causing it. Could be between the pins one side to the other, or in one or more pins' crimps or solder joints. Probably between pin and barrel of each connector, as these types of pins dont' have any spring contacts or anything else, and depend entirely on haivng proper alignment and full pin insertion to get low-resistance connection.
Andersons can be better, as long as they are properly crimped to a wire that is not too large for the housing, so the contact can drift around inside the housing to self-align. If it cant', it cna make an even worse connection than the XLR, sometimes with just a single point of contact along the whole area. This is why people report melted phase or power connectors with Andersons, because the contacts cannot seat properly because of the way the wires are preventing the contact from floating in the housing and self-aligning.
I prefer Andersons to most fo the other power connectors I have tried, but I have only recently been given some Deans and some HK bullets, so once those are tested they might work out better. I also prefer the SB50 dual-contact Multipole (same contacts as PP75) to the smaller PP45s for battery connections, both becuase they can easily handle MUCH larger wires and currents, and because they latch onto each other with more force and are difficult to accidentally disconnect. In my experience so far, Andersons, properly installed and used with the right gauge wire for the housing/contact, and using the right contact/housing size for the power needed, are very useful as they can be keyed in sections for convenieince and safety of various types of connections.