There are some very strong opinions on this thread, and, from some, a very simplistic view of dental health.
Quoting our own, narrow experiences does little to throw light on the causes of dental disease in adults or children.
The three main contributory factors are diet, oral hygiene and genetics.
But, even these can be complicated.
Eg: Diet - most people are unaware that soya milk is considerably more cariogenic (likely to cause tooth decay) than cows milk. Also, the current fad for "healthy foods" can be confusing, so a lot of parents may think a fruit smoothie is a good snack. Not everyone has the ability or knowledge to understand ingredients on packaging.
Oral hygiene - good brushing technique is not instinctive and instruction, especially for parents who may be lacking confidence, is invaluable. Orthodontic treatment has been mentioned and an overcrowded dentition can increase plaque and make brushing/flossing a lot harder.
Genetics - there is a spectrum of enamel strength, at the most extreme ends enamel can be what is called hypoplastic (very soft) with tooth decay almost inevitable or, in areas of high fluoride in drinking water, high resistance to decay.
Wouldn't it be lovely if we could be sure that any child requiring fillings or extractions had neglectful parents, then we could all sit about polishing our haloes and passing judgement.
To address these awful statistics on general anaesthetics for child dental extractions, we need a properly funded child dental health service delivering support and preventative advice to parents.