Not only newbies but the old investors also get panic seeing prices of bitcoin below 20,000$. More panic is being created by crypto related news sites which can more negative news shaking the confidence of the bitcoin holders. In these times, we need someone to keep reminding us that we have to stay strong and threads like this really help us to stay focused and not get involved in panic selling.
The statement that not only newbies, but also old investors are prone to panic will be closer to the truth. Any person can lose their nerves at the sight of a price drop of 70-80%. If news sites are the source of the panic, and you're not sure you can resist a bitcoin panic sell, then the solution is very simple - don't watch or read this news. It will be even better if remove any sources of information about crypto from view for a while until everything stabilizes.
I don't think old investors will panic and sell. If they had witnessed the market cycle at least once, they had a clear view of what will happen next. Unless these old investors badly need the money, they won't sell and hold until the market recovers and breaks another series of ATH. So basically this scenario is just an ordinary event for those who witnessed the previous market transitions of Bitcoin.