They are marked private. Sites like flightaware and flightradar24 honor the request and block the plane. Others, like adsbexchange will not. The FAA r has PIA where you can get a temporary transmitter ID to combat this. However, you still have people matching up your travels with you plane and visually seeing your plane land at an airport and matching it up with the temporary ID.
Big Oil propped up recycling so they could peddle plastics and lie to the consumer that plastics are good for the environment because they can be recycled.