I don't think altcoin is better than bitcoin. bitcoin is the best coin on the cryptocurrency market.
In single cases, altcoins may be more profitable than bitcoin, but this is only possible if you invest in altcoins and sell them at the height of growth that would buy more bitcoins. But this scheme is complex and you need to have a lot of knowledge in trade and analytics.
If we are to talk about profitability, Bitcoin is a safe haven because it is a strong coin. Altcoins could give the same rate but the tricky part is choosing the right altcoin.
On the other hand, if we are to talk about different aspect, aside from the price, profitability, and such, certain altcoins are better than Bitcoin. This would be based from transaction speed, fee, etc.