Wouldn't it be more along the lines of "source available" being a public park that you're free to access but can't monetize by e.g. selling tickets to - while "open source" would let you do whatever you want with the park.
Ironically I think the analogy explains why many people find "source available" to align with their moral compass more than "open source" necessarily does.
Source available is a park where there is some set of activities you are forbidden from doing in the park, but you're never sure exactly which. One day you realize your driveway goes directly into the park, and if you transit to your office through the park you get sued. The park vendor is also trying to get you to buy a home inside the park.
Ironically I think the analogy explains why many people find "source available" to align with their moral compass more than "open source" necessarily does.