There was no evidence about all the spying until 200,000,000 LG displays were sold.
There was definitely evidence, just the mainstream was never loud with it. I'm on the privacy train for more than a decade now, and smart TVs were always considered abysmal in this regard - bad defaults, low configurability, and no alternative firmware.
it's harder to disguise 900mhz radios in devices because it'll be in the FCC listing.