Both altcoin and bitcoin investment involves risk taking, some professionals said that the more the risk, the more the reward.
Altcoin investment will always be risky at anytime irrespective of the bitcoin price movement, if the price is moving in positive direction, altcoin investment if proper research is done is profitable, but if the price movement go the other way round, then it is very risky to invest.
Generally, altcoin investment is more riskier than bitcoin investment.
The sentence told by expert that more the risk more will be the reward is accurate, sometimes people get feared about bitcoin volatility therefore they don't want to accept it but I think that those who think positively about bitcoin will surely understand that wait is must for taking profit and risk can be managed if they understand strategies well.
Altcoins are profitable too but as demand for bitcoin higher therefore people prefer bitcoin more than altcoins and also most of altcoins loss their value due to which the better altcoins loss their value too. Risk is associated with both bitcoin and altcoins but its up to you that how you handle these risk. Try to solve the issues instead of leaving the issue without any solution because if you choose more risky investment and know strategies well and also have patience then no matter its bitcoin or altcoins but you will easily get reward from your selected coins.