There are thousands of data points collected by fellow players, e.g. Color Stacking Fairness Project and Color Stacking and Raids, and explanatory threads of probability, e.g. Color Stacking: The Odds.
If you’re unhappy with those data studies, you could certainly conduct your own.
Ultimately you’re entitled to believe whatever you’d like.
Personally, I believe the game designers, developers, and staff when they tell us that the boards are random.
If I thought they were all liars who were gaslighting us, I certainly wouldn’t play this game.
You’re welcome to continue discussing your opinion, collecting data, or debating whether Small Giant is misleading you — but please do be mindful of Forum Rules, and refrain from insulting fellow players. I’m sure that’s not your intention, just a reminder to be careful in your choice of words.
As I don’t think I can contribute any more information to this thread at the moment other than pointing to the Small Giant Staff statements and player-conducted data studies that we’ve already looked at, I’ll go back to ignoring this thread again for now. If you or anyone else needs me, feel free to tag me. 
Thanks, and Happy New Year! 