"I hope roaming charges come back, because that will mean domestic chargers are more competitive."
Like that is ever going to happen. Those prices are now viewed as the "going rate." When's the last time any of us saw a company, whose primary duty is to make profit for its shareholders, say "Gosh! We've increased our profits by 4%. We should cut our prices and go back to the amount of money we used to make." ?
I think this will be doubly true now networks are having to pay for the rollout of new 5G networks and will want to fill the holes in their balance sheets from that as much as possible.