I don't think it is necessarily that simple. A pickup truck, a few tools, and enough time or savings to spend starting a business is a lot more than many people have. Then there's survivor bias; while it may have worked out for them, how many people did it not work out for. Finally, there's the issue that not everyone can be an entrepreneur. Someone has to actually work at the various businesses that exist and are being created.

Regardless of what you might "think", it really is necessarily that simple. If you try hard enough you can always find plausible excuses for failure.