The quote you have there is in my opinion essentially the number one important thing when it comes to investment. If we are controlled by emotion we will never make a good investment. It's better to be rational and realize that now is an excellent opportunity to buy Steem.
I agree with your reasoning and I do think once people get their forked coin, bitcoin will see a big dump in price while it will raise all other boats in the alrcoin sea. Steem most certainly being one of them with all the good news and development.
In fact I think Steem is just ridiculously undervalued right now