The biggest crypto fund Grayscale Bitcoin Trust bought another 15 114 BTC last week and fund's crypto AUM is almost $10B with 506 000 BTC. In my opinion such BTC stockpiling can be dangerous like a 51% attack but I didn't find any information is Satoshi Nakomoto ever mentioned that.
Nah, 51% attack is different and shouldn't be equate to GrayScale having huge amount of
BTC. I advise you to read the following threads to have a clearer picture of what a 51% attack is:
(a)
How exactly would a 51% attack work?(b)
51% Attack(c)
Bitcoin 51% Attack - Protocol solutions?