Do you know how long it takes someone to sign up on an exchange, go through their KYC process to verify their account, make money transfer from their bank account to that bitcoin exchange, wait a long time until it reaches the exchange and is credited in their account and then eventually after jumping through all the hoops they can buy bitcoin?
There must be investors who registered during the last rally and some of the exchanges accepts UPI transaction and those are instant deposits, Elon Musk is known to create buzz when ever he scribble something in his social media platforms and he has done that in the past when he posted about Doge coin and recently when he advocated Signal, the application saw millions of new users and even the stock of Signal Advance rallied over 5000% because of that, so he does have the influence to manipulate the market 
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