Who uses duct tape for electrical work?
Oh, Larry, that's who.
Car's are exposed to much greater extremes of weather so soldering or some form of mechanical connector is required. You can get away with twisted joints in a house if taped properly with electrical tape or heat shrink. I've opened 20 year old connections where the copper was still nice and shiny but anything that is run inside a cavity / wall / ceiling should be soldered for longevity.
@Wabbit The upper joint in the photo is obviously the one used for wire nuts, but if you're snaking cable through a wall or ceiling the wire nut can catch on a corner or obstruction and get torn off without it being seen. Wire nuts should only be used in place after the cable is run.
My pet peeve in car audio was those guys that twisted wire together like in the upper photo and then wrapped the joint in tape like a wire nut. A bit of hot summer weather to soften the adhesive and the tape slides right off. Then they wonder why their power amp mysteriously blew up.
NEC approves crimped connections, wire nuts, Wago connectors and screwed down, but soldered isn't really a good option for electrical wiring because of low temperature, wind, inability of the electrician to make a good connection and the time needed to terminate- time is money and contractors want to make money, not go back to fix cold solder joints. Wires were soldered in the days of knob & tube, but when ceramic wire nuts came along, that basically ended. Twisted & taped is never allowed in electrical and hasn't been, for decades.
Why would anyone pull wires/cables after the wire nuts have been used?
I would bet that millions of car radios were installed using the twist & tape method and some places used little wing nuts, but they didn't have the wire inside, so they would spin off of the wire when it was pulled. I made the mistake of hiring someone who was 17 and thought he knew everything, but I needed bodies, so....
One day, I saw him using terminals from his own little box and I told him to toss the wire nuts or take them home, but never use them in my shop. He immediately said "No, they work fine! I'll show you". Right. I had been doing car audio for years and he's going to show me that a wire nut is good enough, so he twisted two wires together and told me to pull one end. Sure enough, it came apart easily. I repeated this with freshly stripped ends, but used a crimp cap- the cap didn't release, the strands of the wire broke. He sheepishly put them away and I said "This isn't my shop, it's the company's shop and this is what we will use".