I think it depends on the coin. I'm sure everyone is holding some bitcoins for some years now, and will probably continue doing so, specially with the new halve in 2020 I guess. Solid altcoins like etherium are probably worth holding long term as well. Most other altcoins are probably only good for trade, so I don't think anyone will hold them, and will probably just try to get something out of their pumps and dumps.