Where did you get this information? If this were the case, then I would invest a lot of money to buy video cards.
The developers tell us about the December testnet without miners.
If you think that Ethereum mining will be relevant for another 3-4 years, then why only 20%?
ETH devs said the same thing in 2017, pos would be out in few months, to this date it has not, dont believe what they say, they are together with the manipulators, they have been heavily manipulating eth and other coins price too, all part of a mafia.
Anyway, the issue is not eth going pos, like I said, that will take time, the issue is powerful eth asics miners that are coming very soon. So invest in mining right now seems not bad but as soon the market crash and those asics hit the network, bye bye gpu eth mining. The most powerful public eth asic right now is that Bitmain Antminer E9 (3gh/s) using only 2300 watts. Nothing cant compete with that and will be thousands of them very soon. If eth devs had moved from ethash to progpow or something alike then things would have been very different right now. It would definitely be a good idea to invest in mining without worrying about anything, right now invest in mining is suicide, 20% to gamble is not bad.
Also as soon as eth asics hit the network and eth price crashes to hehell, gpu miners will have to move to other coins and will be no coins to move to, most will have to sell their gpus at loss and very cheap, will be a huge influx of gpus in the market. It will be the inverse of what we see at the moment. You trolls have been warned. All cryptocoins are overbought, people want profit and most are in no profit at moment and soon the distribution phase will happen, there is a limit those people will hold cryptocoins, they know this market is too volatile, stocks are kids play compared to crypto market, anyway, in this crypto market, you can become a millionaire or a peasant overnight.
Most of the altcoins I have at the moment lost 70% from peak already and no signs of any going up again or a reversal. If this keeps going up soon will be 99.99999999999% loss from top ehhe just like 2018, dangerous gamble, I created an eth sell order at 4.89k and almost hit it, got to 4.8k, bad luck I guess.