@jokiin @Pier28 @niko etc all work within the camera field...it's our job to know. We talk to factories, developers, engineers, SoC providers etc so we know a lot simply from 'networking'...
@Mtz knowledge seems to come from extensive reading and following the area. Ambarella post a lot of their information online as do HiSilicon, Novatek used to but I'm not sure they do any more, so the best thing to do is to read up on what you can.
The thing after that just comes from testing, reading, and analysing. A true 4k camera is not going to cost 60usd just yet. The lens and SoC are to highly priced so that should be a massive red flag. Second of all the 96660 has been out for about 2 years or so (in cameras) so realistically that isn't going to have 4k...
I guess there's no place you can just 'go' and read up on this, it comes from reading forums (not just DCT and RCG), documentation, and talking to factories etc.
One thing I would say, a lot of these companies don't like to 'broadcast' their announcements (for obvious reasons) but almost all of these companies are publicly traded, and as dictated by law they have to release certain information in annual and quarterly briefings (anything that could affect profit)...as such read annual reports etc as you might just get a mention of something important, I know that's where I've picked up some important information in the past.
Hope that helps.