About your title, I don't think anyone knows when altcoins season will start, we can only but trade and hold the potential coins we trust in. Secondly, about those two exchanges, while comparing few years ago to now I tend to understand your point, they were huge and widely known with most projects running after them but nowadays the circle has changed and it is now the likes of Binance, OKEx, Kucoin etc. Hence the reason it's good to embrace change and innovation.