you don't have to worry about miners' revenue. when miners were getting paid twice the current amount of bitcoin for their work (ie. 25BTC) they were earning $6,250 per block but now with half that amount of bitcoin (ie. 12.5BTC) they are earning $108,000. even if we had 4 halvings tomorrow they are still earning more money than 4 years ago.
You're treating a serious issue quite lightly
Yeah, the miners were earning only that much, but do you want the network to be back at 1PH at a time when with just 50mils$ worth of gear you can launch a 51% attack at that hashrate?
Miners were paid back in 2009 half a gram of pizza per block, would you entrust your money to a chain that can be attacked by a 1080ti?
At the time you mentioned their expenses with power consumption had to cover (assuming best gear available) 33kwhx70k miners per day, right now if we assume the same gear it's 70kwhx1.5 mils, 40 times more.
This is what happened to shitcash and shitvision after the halving:
Both coins can be attacked right now with 51% with only 10k s19 miners.
Yes, you have to worry about the miner's revenue!
If they were making 10 cents with 6 cents expenses and 4 cents in profit now they will make -1 cents in profit and shut down.
And with every mining gear shut down the security of the chain is going down and there is more gear that can be picked cheap just for..."fun".
