The exact same thing that a hundred million hookups did before these contraptions came to market. Having a go, no-go protective device is an advance however there was life before surge guard, smart chargers, slideouts, AGM batteries and penicillin.
I will offer this: it is my most humble respectful opinion that today's RV's have about a hundred times the malfunctions and repair expenses as rigs did thirty years ago.
I started RV'ing to relax and enjoy myself in an environment several times that afforded by tent camping. Today's RVer seems to be in a perpetual race to purchase incredibly complicated rigs then keep adding stuff until a trip seems guaranteed to utterly malfunction and fall flat on it's face
But I have far less tolerance and patience than most.