Malis and Dutch Shepherds/Herders and to a lesser extent, heavy working type GSD's are the latest 'must have' 'hard' breeds to own for a particular demographic who like to train 'protection work'... ie biting people for funsies.
For those who take competition bite sports seriously and keep these dogs appropriately, sourcing them from good breeders etc, thats not an issue... but its becoming increasingly popular with people who have zero handling skills, knowledge, facilities or business doing this, with dogs from VERY dodgy breeders (basically bred to want to bite like maniacs from as young as 5 weeks old) - controlled and 'trained' using shock and prong collars and focusing heavily on the 'grab and bite a person' aspect and not the 'let go when told to, immediately and without question' aspect.
In part this is a result of lockdown, in part its the huge rise in social media flashy trainers (almost all male 'alpha' types!) promoting such training and activities. I think theres a good strong link between this and toxic masculinity 'be teh alpha, control a powerful scary dog that bites' too but thats my own personal theory.
The dogs they're getting (and fucking up, causing accidents with then euthanising or just dumping) are horribly bred lunatic bite-a-holics, they LIVE to bite, they don't just like it, they don't want to do anything but bite and bite people at that (ok they're biting the sleeve or the dummy but the way these morons train... they're biting people, including their owners, as part of training).
Rescues and general trainers are seeing a huge rise in Mali/Working GSD/Dutchie types (often mixes, rarely papered) in pet homes where the husband/boyfriend has bought the dog for this and then the wife/girlfriend has realised that this is not the safe pet puppy they were told and then they're asking for help which often just isn't possible as they do not have the means to meet the dogs needs or the dog is neurologically beyond help.
Again... it isn't the breed itself, it is the people. The common factor here is stupid, dangerous people.