If you write and release open source code, the license will have no impact on your ability to do so. You can write and release your contributions as BSD, and include others BSD or GPL licensed code. You can write and release your contributions as GPL, and include others BSD and GPL licensed code. If your intention is to release source code and share your knowledge and time with others, the license is not going to effect you.
If your intention is add restrictions on other peoples work, then you are taking away the choice from others who want to read and modify the work. This won't benefit other developers, nor will it share knowledge or contribute to developers projects. Making it closed source closes any sharing, modification and redistributing of the work.
You demand to have the choice to take away choices from people. I choose to have the choice to take away the choice of taking away choices from others. That is my choice, and you are not allowed to restricting me from having it.
If you don't take away the choice, I won't either. My usage of GPL is only needed for as long others want to make proprietary software and remove choices from people.