[SNIP]
...hodling might be considered as long process of gambling???
I guess it might be yes. If you are not monitoring the crypto market price then it would be gambling but if you know you can simply sell your holding coins in order to cut your loses. However, this is a case to case basis. If we compared both these holding and gambling, the worst I guess is gambling rather than holding. But when it comes the whole concept and outcome they are both gambling that risk money.
They are indeedly both risking money that's why they have similarities and also differences. To explain the difference in a simpliest way, investing is a boring way of risking your money while gambling is the opposite which is why gambling is fun but more terrible for outcome for every mistake you make than in investing. You could be a millionaire and poor in gambling within a minute while in investing, that's not going to happen since it acquires a lot of time to see the outcome.