Do you believe that certain tech with the potential to be humanity-advancing, has ever been shelved, kept secret, and/or suppressed by existing power groups in order to maintain certain power structures and control?
This sentiment is common among CT crowds, but even plenty of your regular everyday folk seem keen to the proposition.
Here's a YT video with some proposed examples to help illustrate the idea of the thread:
Personally, I think you'd have to be pretty naive to think it hasn't happened at some level, and likely more than once. But with that said, whether or not an actual water powered car or free energy device was ever truly created and suppressed, I couldn't say. Maybe, maybe not.