Just purchased the well respected 🤣 Wolfang GA420 action camera for $140 on Amazon - specs indicate 4k.
Sometimes these cheap gadgets on Amazon etc pay off but I returned it after 2 days because of terrible sound, poor video when moving, unable to transfer to app over wifi and it kept cutting videos to max 19 but often 10 minutes despite indicating they could be unlimited. Build quality was good but that's about all.
My son did an experiement taking a frame of 4k which he insisted was not 4k but likely only 1080p just being encoded as a 4k file. He proved this by using the resolution adjust feature in photoshop and duplicating one Frame to 1080 p and then playing both 4k and 1080p back and forth on a 75" TV and showing there was no visible difference. Got me thinking was his methodology sound?
You do know that hindsight is not much of a super power.