What will happen with staked ETH on the POW chain after the fork?

As the POW chain will never 'merge' what happens to all the ETH that is already staked on the POW chain? Will tokens such as stETH and rETH be worthless on the POW chain?

I'm wondering if it's worth swapping my rETH and stETH back to ETH before the merge to get more POW coins that I can sell for additional ETH after the merge.