That day will never happen
Lazy stuck in mud thinking to think BTC can't be beaten in market cap. Especially when we are such a new industry, its like saying PAINT is going to dominate graphic design for the next 100 years. lol
I can see XBY type platform overtaking as the multiplication affect of software using the same currency BUT I don't see that even if that happens as BTC losing its dominance even if not in market cap.
Bitcoin was designed as digital Gold...its was never supposed to be VISA. Ask Nick Szabo what he thinks AKA Satoshi.
The question of dominance based on market cap is pretty stupid, its like saying what is more dominant the Russian Ruble or the Yuan. Its more a question of which one is more stable, reputation etc not just market cap.