While I agree it's not the right time to build a new rig, the drop off of mining earnings from today shouldn't be 40%.
If I'm wrong here, please let me know, but the block rewards would be a base minimum of 2 ETH (like today) plus any tips. So even if there are no tips, a block reward will still be 2 ETH.
For ethermine, the most recent block rewards are in the 2.1 to 2.4 range. That would be about a 4% to 15% drop to 2 ETH. Even the higher rewards of 2.6 would only be a ~23% drop. You have to get into block rewards of 3.3+ Eth to see a 40% reduction.
So it will have an effect, but it's not going to be nearly as bad as some people think. Plus there's the probability that the value of Eth rises.
With all that said, right now, $2k USD would be better spent on Eth directly instead of a GPU to mine it.
I say is better in GPU-s as for the long term you can always switch algorithm if the Eth profitability falls that much by 40% which I highly doubt it will.There is Ethereum Classic,Ravencoin and Ergo coins which are still very profitable to mine.If the profitability goes down like 5-15% will not be a big deal if we have a price increase of Ethereum then we are still in profit and this indicates that in the long run can be a good choice to buy GPU-s if you can find them cheap enough which unfortunately is not the case as of yet.Personally I was being pushed by a friend to just buy Ethereum in February 2021 but I insisted on creating a mining rig and I am glad we did because until now we have accumulated 1.3 Ethereum in total which is not bad and we continue to generate near 0.01 Eth daily with almost 300 Mhsh of processing power.
If anyone thinks that Eth won't move to POS within a year, then go for the GPU. A 3090 should take almost a year to mine one Eth. (MSRP matters there.)
I started in February too and I knew the short timeline.
I plan on mining other coins too, but right now, if Eth goes away and miners all move to the other coins, that profitability will drop significantly. Hopefully something else pops up but there's definitely a "green" push in the crypto space.