I think that various methods for decreasing water usage has a chance of becoming very popular. Examples: Do we really have to use toilets that flush with pota

I think that various methods for decreasing water usage has a chance of becoming very popular. Examples: Do we really have to use toilets that flush with potable water? Can we either use gray water for this, or come up with alternative solutions that require less water? Do we have to shower using potable water? For example, I’ve seen technology for reusing shower water. See e.g. https://orbital-systems.com/ https://orbital-systems.com/ for one possible solution in this space. There are probably lots of other examples where the use of (potable) water could be reduced.