But when I look at this, maybe a bit worried,
There is absolutely nothing to be worried about, like you said, whether this guys sell it or not, the price of bitcoin will always fluctuate for several reasons, and should I tell you something?
It is actually better for the price of bitcoin to go down because someone dumped a bag, than for it to go down become a big exchange was hacked or went bankrupted - for the first, the price will quickly recover back to its normal price, but for the latter, it will take very much time for the price to recover, simply because, several people are selling in other to cub their loses - and some selling out of lost confidence.
I don't know how many people in 10 years ago still own a lot of Bitcoin until today and sell it at the same time. So What you're though?.why are they selling it now, and not on ATH acouple years ago?.
It's not like we usually know what the all time high price of bitcoin will be before it reaches that price, if there is a way for us to know, do you think anybody would want to buy bitcoin at the all time high price,?
Think about it and I believe this should answer your question.