Do you need all these solid facts and evidence to prove a point to your friends? You know what you believe and have already told your friends what you know about bitcoin. If your friends are really into crypto, they'd know which coin is the leading coin in the crypto world,  especially this period that bitcoin's price has hit 100k+ and now around 93k. Which other coin comes close?

Your friends know what they saw in altcoins,  allow them to do their things if they won't listen to you. If everything fails, it's their decision and not yours. Maybe they would learn more about bitcoin when they make mistakes with their investment choice. Some people learn better this way .