Grayscale is a good news but not enough good news. It is just one company buying a ton of bitcoin but it is still one company. What would be good is a lot of companies like grayscale, generally wall street type of investment bank sort of stuff would actually be good to actually buy bitcoins. With one of them it is definitely good, it is better than having zero of them, however having just 1 versus having 100 is of course no question as well.
I do believe that there is a lot of companies who are investing into bitcoin that is not showing as clearly as grayscale, I just hope that one day they will disclose all the billions of dollars bought between those wall street companies as well. One day we are going to look at this day and think how small we were, until that day we just have to be happy with even just one company being so pro-bitcoin.