It was very interesting to read your post. Probably, the number of the cryptocurrencies will be sufficiently cut in the future as you say. However, I think, more than 50 altcoins will exist.
Nah, with a lot of people taking their interest on crypto currencies, I don't think that it will be cut. Also, 50 altcoins is a small amount. There are a lot of crypto currencies in the circulation especially these year, as of 19 August 2018, there is over 1600 and growing. That is a huge number of altcoins and I think that will blow more in the future, just you wait.