We’ve got a 3 year age difference between our two kids. When the eldest stopped needing naps we said that he didn’t have to nap but that it WAS quiet time so he could do puzzles or look at a book, or colour.
Obviously your options there are a little limited by the age.
Kind of a side note but:
Kids are expert negotiators/ manipulators, so they will push you to your absolute limit if it gets them what they want. The reason they tantrum is because it gets them what they want. It will take many unsuccessful tantrums before they learn that tantrums don’t work. Make the best way for them to get what they want, something other than a tantrum.
I think a reset is in order. I would try a few days with no nap to try to get the night bed time more sane. Then introduce quiet time. Maybe say “I’ll read you 3 books, then it’s quiet time”. They don’t need to have their eyes closed, just lie quietly in bed, it doesn’t need to be for very long, just introduce it as something that’s not a big burden but is non-negotiable.
Good luck, it’s not easy.
I don’t give money to panhandlers because I don’t like being solicited. (Also why I don’t buy things at my door, or via telemarketing) however I do support the idea of programs distributing funds directly to those in need.