People have a right to have their corpses treated with dignity, and the bereaved should be able to remember their loved ones long after their passing. However, the harm the funeral industry does to the environment cannot be ignored.
In conjunction with a shift towards less polluting methods of disposition of remains, I believe all nations should feature opt-out organ donation systems rather than opt-in ones. In addition to the benefits this would have on patients requiring organs, this could help people stop fixating on the sanctity of corpses (especially when you may not have cared all that much about the person), and dismantle stigma around discussing death. People might really be amenable to getting rid of anti-ecological death practices, if only we start to talk about it: they need to know there are options that don’t involve being mounted in formaldehyde like bugs, or being reduced to ash and dumped in an urn for your family to forget about.