News is news.
This is, for Bitcoin certainly good news.
Whether it is truth or lie.
If Mark goes to the crypto ( Coinbase or something other ) this is a clear message to the whole world. "The big Facebook is giving money where Mark it think will not to lose it."
Many undecided will easier to make a decision.
Small and big....
And if anything like such happened its clear indication for crypto field that it is asset class and everyone will start trusting it lot more .