I dont think so bitcoin will change everything...because there are other things that bitcoin cannot change...like cashless world,gold investment etc. Bitcoin is profitable but there are also other cryptocurrencies in compare with bitcoin...
There are many other currencies which are competing with bitcoin but every time they fail to stand next to bitcoin, all their efforts and attempts result in vain.
I can't agree with that. While most alternative currencies aren't worth a dime, the top altcoins make tough competitors to Bitcoin by now. And if Bitcoin fails to scale successfully in the nearest future, it will likely lose its status as the king of the cryptocurrency world. Personally, I don't see any significant difference, for example, between Bitcoin and Bitcoin Cash. Therefore the latter may well take Bitcoin's place in 2018 if the former stagnates and doesn't show substantial growth. But this growth is impossible without things being improved in respect to transaction costs and confirmation times.