My 2 cents comes from the computer biz where ALL printed circuit boards (PCBs) are soldered, and everything off-board from the PCBs is crimped.
Soldering PCBs works because they live forever in a controlled environment at 40% humidity, controlled temperature within a narrow range, managed power, etc. It is also extremely economical to solder hundreds of components from integrated circuits to resistors to relays, etc, by passing a component loaded board over a wave of molten solder on a machine to (a.) hold all components in place and (b.) make a proper, solid, electrical connection and (c.) get it all soldered in seconds per board.
Away from the boards, connectors are chosen for a bunch of things like environment (including humidity management), power or signal requirements, reliability, etc. Their terminations are always crimped, except in some copper-wire instances of the phone company when they used a compression bus where they pushed a wire between two jaws on the connector bus to make the connection. Since the arrival of Fiber Optic Cables that corrosion-potential method has been going away (Danny could give us insight, here). I can't remember, in 30 years of building electronic assemblies, seeing a soldered connection away from the PCBs.
Same goes for cars - The electronic gizmos are all wave soldered but all of the wiring, everywhere in the car, is crimped, always by a crimping machine that is cost prohibitive to hobbyists. Hundreds of millions of cars are a lot of data points (except for those British ones running smoke-filled wires and two-fuses-per-car from Lucas). My data point is that 98% of my car wiring is crimped using a ratcheting hand crimping tool like this:
https://www.amazon.com/Klein-T...ad_source=1&th=1
It does red, blue and yellow crimp connections, is adjustable if you need to, is easy to use and the only time I've had trouble was when the wire was too small for the crimp connector and it pulls out (operator error). If you're doing an entire car and want solid connections, get one.
If you want to insure a connection is waterproof, position some shrink tube over the crimped connection, shoot dielectric grease into both ends of the shrink tube, then shrink it and clean up the excess. I've done that on my car for all of the outside lights and such that could get wet and they've been trouble-free for 20 years.
