[roadnottaken]

Maybe it wasn't voluntary 25 years ago, but there are plenty of options today and most scientists still send most papers to for-profit publishers. You can argue about the culture and career pressures that influence those decisions, but the fact remains that there are alternatives that are still not commonly used. Other fields have managed to get around this (eg ArXivX in Physics) so it's on biologist/chemists to figure this out, too.

[beevai142]

The journal choice is still not fully voluntary. Each field has certain flagship journals, and you are going to publish in them because they have large impact on the prospects for future career. The journals are flagships for historical reasons --- it takes time for a journal accumulate credibility and attract high-quality papers. If the flagships in your field happen to be owned by Elsevier, the you are going to be squeezed. Granted, the existence of arXiv and others alleviates the open access issue, but not the issue of crazy profit margins of the publishers.