No?
Ye? If so, how big???
The size of effect will totally depend on how "controversial" his/her/their political/environmental/etc views are.
Also: could he be able to change the bitcoin security or sonething related???
No. If a single person/entity could change Bitcoin then Bitcoin might as well just be dead to start with.
Kind new around, and i never heard/saw nothing about it…
You need to do more digging.