The only influence Satoshi has right now is the power to cause fud or fomo from his reappearance into the space and maybe air his views on what's currently ongoing in the community but I doubt that'll even happen. Satoshi knows his present won't be best for bitcoin that's why he disappeared and it's a good thing.
Satoshi can still lower the price of bitcoin in no time (if he want and he come back) because he has some bitcoin in his wallet. If all the bitcoin Satoshi owned were sold on the market, the market would instantly turn into a bear market and that would be much worse than the whale could do.
I dont doubt Satoshi's capacity as a bitcoin creator, and I believe he can still do some thing with bitcoin and the community and this is an unsolved mystery since then and that is his existence.