It's more profitable for LG to sell your data to advertisers than to build and sell the TV itself

The negative effect is the exact sky high prices that Americans keep complaining about. The point of all that advertising data is to nudge you towards accepting higher prices or buying things you otherwise wouldn't.

Every dollar of revenue in the advertising industry is money taken from consumers and spent on unproductive waste to get you to spend more money instead of anything like making a product better or investing in capacity or researching and developing new products.

Google makes money by making you spend more money. Facebook makes money by making you spend more money.