I guess altcoin season has come and pass in this year, and people are hoping for another season that will be greater than last season that makes many altcoins investors to double up their profit. You can see the dumping that is going on in the market and is affecting altcoins price too, because is a sign that many altcoins price will reduce for some hodlers not to sell their altcoins in this season.
I don't think there is anything left this year because the price of bitcoin keeps depreciating and that is what as also affected the price of altcoin and have stopped them from growing, since Bitcoin is the main thing that affects the price of other altcoins. That is one good thing about investing because anytime the price is down it will recover even with a greater ATH so there is always this confidence given even if the the price is going down. Instead of panicking, this period is not a good time to sell and periods like this you buy more and hold. This how to make money out of the market. Selling out if panic will result to loses.
There will still be another altcoins season but it will not happen this year, because the price of BTC is still falling to make other altcoins to remain in red light not to encourage altcoins investors to have the mind to sell than to buy little altcoins and hodl.
This year is finished already and before another season will come it might be next year and even the next year there is no assurance and because you can not predict exactly what will happen tomorrow. So we can only buy and eventually when it happens then that is good and if it does not happen then you hold that is the easiest way things can be done. As far as they want to buy and hold they should go ahead.