You are right, because everyone has a choice to make and so knows what works for them better, there's actually no need trying to convince someone who have a different perspective about something different from yours.
Apart from everyone have a choice, the way and manner OP explained the scenario is not a good thing to do even if you have made millions and that your friend is yet to invest, there is no need to blast him publicly because Bitcoin transactions itself is not legal in Nigeria.
Bitcoin investment is a choice and no one should be blamed if they don’t feel comfortable to invest; some of us wants to invest but they lack capital to start the investment while some have the capital but don’t feel comfortable to invest due to fear of market volatility.