Ethereum Classic launched in 2015 and has a 5M20 monetary policy stating the maximum supply of ETC is 210,700,000 implemented by ECIP-1017. Currently 143,276,000 ETC coins have been mined, making up for roughly 68% of the total supply. Due to ECIP-1017, and the fact that we are in Era 3+, there is a 20% reduction in block rewards every 5,000 blocks. This is scheduled to take place on April 25th 2022 as we approach block 15,000,000. After April 25th the block rewards will decrease from 3.2ETC to 2.56 ETC per block. The estimated next Era, Era5, will take place around May 2024.
Is this Going to Decrease Mining Profits:
More than likely you will see a decrease in mining profitability. You will be mining less ETC and the only way profitability will stay where it is, is if the price of ETC goes up by 20% and the network hash rate stays relatively the same. Currently as of 4/19/2022 the price of ETC is $37.07 per coin. If ETC goes back up to $44.48 per coin then mining profitability will stay relatively the same. Currently a single 3080 makes $3.14 a day on ETH and $1.97 on ETC. After the fifthening the profits on ETC, if the price does not move up, will be around $1.57 a day. With ETC still being less profitable, and the ETH move to POS being delayed I don't think we will see many miners switch over. This means there is a huge opportunity for smaller miners to capitalize on mining ETC and earn a fair amount of coins before other miners make the switch.
ETC Network Hashrate:
We can see that leading up to the fifthening there hasn't been a dramatic increase in network hash rate. This is due to the profitability and there being other more profitable coins to mine and most of the hash rate coming from GPUs with less than 4gb of memory. Although ETC did spike up to $140 last year, I don't think this news will be met with the same price action.
Can ETH Asics Mine ETC:
Application specific integrated circuit miners are dedicated to mining only one coin. However because the EtHash4G algorithm is extremely similar to EtHash most of these ASIC miners will be able to switch over to ETC by running a firmware update. Some of the older miners with less memory have already switched over to ETC. With the DAG size being so low, for lower end GPUs to get on the network and prevent attacks, these ASIC miners are still able to mine ETC and should be able to until 2024 when the DAG size increases. ETC has also proposed ECIP-1049 or SHA-3, which is a network upgrade specifically for ASIC miners. This would still allow GPUs to mine on the network but allow more ASICS to mine ETC, however this seems like it was proposed when the ETC network attacks were happening. There hasn't been much news in terms of ETC switching over to SHA-3 and the newer EtHash ASICS wouldn't be able to make the transfer over to ETC if SHA-3 were to be pushed.
Also Check out Best Mining GPUs Benchmarked on ETC