I specifically didn’t write any btc amounts in the calculation only dollar amounts. Since miners will pay their ASICS and electricity in dollar. That the value that matters.
You are wrong and since you like to use USD values I'll give you USD values.
When bitcoin started miners were earning $0 per block. We fast forward to each time the money they earned was cut in half (dropped 50%):
- 2012-11-28 they were earning $75 per block
- 2016-07-09 they were earning $8,500 per block
- 2020-05-11 they were earning $61,875 per block
- 2021-03-09 they are earning $309,525 per block
All the above values are with 0 fees per block!
Although the price rise is not guaranteed but there is also no reason for the growth to slow down let alone stop. So historically speaking we have no reason to believe hashrate would drop just because profitability of mining bitcoin would decrease.
You also make the mistake about hashrate; it doesn't rise only with price (profit miners make) but also it increases with advancement of the hardware used to mine bitcoin (ie. new and more efficient ASICs).