your reasoning is a bit off.
i am not saying blocksize debate had 0 effect. but i am saying it is not the main reason.

these pumps and 100%-200%-500% increases is nothing new in altcoin market. it has always been like this.

in coinmarketcap.com just click on the charts and set the time-frame to all (more than a year) you will see that the #pump pattern keeps happening every now and then in each coin.