Is there any benefit, at all, to docking tails or cropping ears on breeds where it's common (cane corso, doberman, rottweiler, etc)? No, right? I have to admit I find the look attractive, but I wouldn't want this if there's nothing in it for them. This is mostly curiosity, I'm not looking for a dog currently but I am trying to get my ducks in a row and learn stuff right now.
Cropping ears and docking tails is something that *TRADITIONALLY* was done on "working class" dogs. Those you named are the primaries, The reasoning is at least halfway sound - Long tails get damaged/infected/end up being amputated in the course of treatment, at a higher rate among these breeds (never mind that the tails on these breeds are USUALLY pretty ... what's the word I want... "wimpy" will do for lack of anything better I guess - These breeds usually have "wimpy", easily damaged tails compared to other breeds where the tail is more robust. So essentially, docking the tail is, in at least one way, "mercy" - No tail, no tail injuries to treat, become infected, require amputation.
As an example, I once knew a lab - normally VERY rare that they get docked. She was closed inside while owner made a store run. Owner came home and found the walls spray-painted with blood from floor level to about the four-foot-high level, and the dog had a tiny cut at the end of her tail. Best explanation/reconstruction anybody could come up with is that when she was closed in before owner left, she wagged wrong, hitting the wall hard enough to cause the nick in her tail - maybe she whipped it against the wall splitting the skin, maybe she hit a corner, maybe... Nobody knows, but it's the best guess available - and it caused the nick in her tail. Then, while the owner was gone, she wandered around the house wagging, and in the process, splattering blood in all directions, much the same way that if you turn off a garden hose, then swing a few feet of it back and forth, you'll fling water all over the place.
Edit to add: She ended up docked just as tight as a dobie or rotty, because she kept wagging it against walls and whatnot, breaking open the wound and having it get infected, go gangrenous, and have another joint worth cut off the end until she was down to "nothing but a dobie-like stump", when it *FINALLY* stayed still enough to scab over and heal.
Ears are similar, though mostly used in "badger" and "rat" dogs - The ones, like Dachshunds (wiener-dogs), sent underground into badger sets and rat burrows and similar to kill and/or flush out the occupants for whatever fate awaits them. Ears are vulnerable to injury in such situations - much more so than "always above-ground" dogs. So it became routine to trim 'em down - In the case of dobies, a "natural" dobie is a flop-eared beast that was originally a hunter/herder dog, subject to ear injuries, and *VERY* prone to getting loaded up with burrs and similar as it goes through brush in pursuit of its duties. By trimming them back to an upright form, you get fewer and/or less severe ear problems. Similarly, for the "underground" dogs, getting loaded up with who-knows-what-might-be-encountered inside a badger set is greatly reduced, reducing the chance of infection due to having "gunk" trapped in 'em, and lessening the damage that might occur as a result.
Similar applies to draft horses with docked tails - If you've *EVER* been on a runaway due to one of your team getting its tail up over the lines, you'd be likely to demand ANY driving horse be docked. Never mind that a long, flowing tail on a drafter puling farm implements is a danger - Imagine the train-wreck if the tail gets pulled into the pickup head of a hay baler, or corn cutter... <shudder>
Yes, tails can be braided up. This is practical for todays "hobby" critters, but back in the day when you and your team going out *NOW* could be the difference between getting the hay in for the winter, and having to shoot them come January rather than watching them starve 'cause you spent time to do the braiding/wrapping and the hay was ruined in the field, rather than safely stowed in the barn... Well, you do the math...