If you hold less than 1.5/2 BTC , do not buy a ledger wallet or others stuffs like that.
I don't understand this advice. A ledger costs less than $100. I would say if you are holding even a few thousand dollars worth of Bitcoin, especially long-term, then a ledger or other hardware wallet is a good investment.
that is why i always try not to give an exact number because it is different for each person. some may go with higher amounts and some with lower. but i think a better factor to determine whether or not to buy a hardware wallet is your usage not your amount.
for instance if i want to hold bitcoin i put it in a paper wallet which is my encrypted key on a piece of paper which i have laminated. i also have a back up from it. but if i wanted to spend from it often enough, like a big trader moving big funds to and from exchanges hardware wallet is more suitable.