do you not see these issues in UK rescue dogs then or dogs bought as puppies?
Some issues like poor recall can be an issue with any dog, regardless of background, but I've never encountered a UK rescue that was terrified of a lead, collar or harness, no. I have seen it in multiple overseas rescues, though.
The most aggressive and reactive dogs ive seen round here have been chihuhuas bought as puppies. A couple of lhasa apso types that are mental. Some cocker spaniels. A springer. I know a couple of foreign rescues that bark, but I dont see any correlation between foreign rescue dogs and difficult behaviour, and I know a lot of dog owners round here
I'm not saying that only foreign rescues behave badly - apologies if it came across that way. Of course poor behaviour can exist in dogs of any breed and background - it would be silly for anyone to suggest otherwise.
Its not as if these rescues dont do checks or tests, because they do. My garden was checked. My house was checked. They wanted to see how the children were with the dog and how the cat and dog reacted to each other (the dog was already cat tested beforehand too). The rescue owner chatted to me for quite a while. They turn down plenty of people too
TBH, it sounds like you got very lucky, because they don't all home check, ask questions and make sure the dog is tested with cats or children. I occasionally walk a dog who is from Cyprus - he came straight to his new home after a 3 day road trip and ferry crossing. The owners weren't home-checked and he wasn't given a chance to decompress from his journey before being thrown into a new home.
The rescue told his owners he was good with cats (he's not, and has terrorised their resident cat and bitten her). He's fine with their dog but awful with strange dogs on walks - he will snarl, snap, lunge and react to every strange dog he meets. He's fine with people but very, very overexcited and he would be awful in a home with young kids or with inexperienced owners.
He's a lovely dog overall, but he needs a LOT of work and if he was homed with small children I could see it going very wrong.