Social media is a means of disseminating information, both vital and non-vital information. While cryptocurrency is a digital asset, whose price movement is dependent on the activities of the traders, that is, the buyers and sellers at large. So it implies that if the majority of people decide to sell a crypto asset, the price will fall drastically and if the majority of the community decide to buy a crypto asset, the price will increase drastically.
Given that the above explanation holds true(which is usually the case), if a major social media influencer who is well respected or even the project's social media handles decides to give out a vital information concerning a particular coin, if this is in favour of the coin, it could impact the community followers of the personality to buy a crypto asset, thereby increasing the price and if it's against it, then it will mean that there's going to be a fall in price, so yes, social media does affect cryptocurrency, it can either boost or suppress the morale of the community to buy or sell an asset. As case study is Elon Musk's tweet that usually do increase or decrease the price of crypto assets.