Why is South American football so low scoring

Always been this way. More red cards than goals in a lot of games. Most South American football is absolutely unwatchable.

anytime I see a team with CD in front of their name I don't back goals, CD must stand for Closed Door

Camping Defence

You have only to look at the Villa Forest match yesterday
to know that in the premier league the defensive ability is almost non existent and full of errors
that silly goals are inevitable .. its laughable
South America they defend properly .

I have little knowledge of South American football but wondered if they like to play it out from the back as we now do?

Not all leagues are low scoring. The likes of Chile, Bolivia, Peru aren't really. Argentina is pretty bad. I reckon it's because conceding the first goal is often fatal and home/fav teams play cagey and don't take risk until later in the game, away/underdogs play for the draw. Defenders get away with being more physical too and if you have a modicum of attacking talent in the likes of Arg or Brazil you go abroad where there's more money.