Perhaps let's brainstorm ways to solve this. How can we incentivize joiners to projects? How can we both appreciate the founders and starters, and the later joiners who are necessary for the project? Perhaps if we encourage our own community (tech) to give serious weight and appreciation to all contributors, that will move things in the right direction.

Also, the creators of projects can do their part by sharing the praise their projects receive with their contributors.

What other ideas do folks have to encourage joining rather than starting?

Maybe assigning specific "ownership" (responsibility for, overall credit for) of some portion of the project to long time contributors over time?

Exactly. Also it's incredible how many working professionals (as evidenced by this "movement") don't understand why companies pay for software to these SaaS companies.

Ironically attaching your company to a movement like this will deter people from using it.