Why can't I get a TRUE Deep cycle battery anymore?

For every attempt to do the right thing, there will be workarounds which will have the opposite of intended effect.

Make a law forcing this or that, and those making money by polluting or whatever, will goto great lengths to find away around it and often these attempts will be more destructive or have other hugely negative inpacts somewhere else.

Human nature, and today's upcoming generations are more selfish and self serving than ever, and money/max profit has never been a louder motive.