well i think bitcoin is good but it's not perfect, it will never be because there are many different opinion what was the original vision of Satoshi Nakamoto. Recently, the biggest problem were fees which were extremely high. Fortunately it looks like this problem is solved for now. SegWit adoption is rising, Lightning Network is almost there and every aspect of bitcoin need to be improved. If there was no improvisation, then bitcoin will be left by the holders because many altcoins other than bitcoin offering a new better features than bitcoin