Some of us were perfectly capable of watching too much TV and eating too much sugary and fatty foods as children and not continuing that lifestyle into adulthood.

Not everything you do as a child informs and solidifies your decisions and lifestyle as an adult.

While I agree, and manage to live comfortably without TV in my life, i find the sugar addiction for me is still very real (despite a conscious effort to avoid it). Having said this, I don't believe it is directly related to childhood as much as it is just a fact of the food that is readily available to us as adults.

Young people and children still watch a lot of "TV" but a big share of it is done via streaming. Also, judging by how many young couples make their kids watch "TV" on a tablet or phone while they are waiting on some appointment (situations where my generation had to actually stay put or find creative ways to pass the time) I think the case can be made that children are actually spending more time in front of the "TV" than our generation did. In any case they are spending more time in front of the now ubiquitous screen and so may very well end up with a bigger waistline too.