This doesn’t make sense. As i made a lot of mining and electricity cost calculations in the past it isn’t working like that.
First of all it doesn’t make any sense to turn off the asic 1 year ahead, don’t forget currently all miners are mining and paying a fee that was clear. Nothing changed at the moment and there is no evidience that every new miner or added hardware to the network is allready aware that a new dev fund is planned.
Second. The mining hashpower won’t be affected by a new dev fund anyway. All that happens is that miners that currently mine at a minimal or small profit in higher electricity countries and regions get forced out of ZEC mining business, while at the same time these get replaced by miners in low electricity countries as these can with (for example) half of the electricity costs can take a bigger decrease in mining block rewards than these that pay for higher electricity costs. Means the hashrate chart is not representing anything at the moment.
Let’s be honest made, when we both for example than back bought our Z9 minis (i think we than back bought them nearly at the same time) we haven’t been aware of an extension of the FR or invention of a new dev fund.
There are othe coints that can be mined on the same algo. I made a list (no longer updated) where you can see all coins mineable by asics on equihash. As i don’t mine my own anymore i have no idea if some of them are still profitable or not.