Personally, I have my doubts that the mere fact that a person who presumptively has been in bitcoin longer and presumptively accumulated a decent amount of BTC at lower prices would not necessarily panic during various extreme BTC price dips.
Sure, there should be more systems in place that contribute towards longer time bitcoiners to figure out how to manage their bitcoin portfolio and other parts of their cashflow, yet I think that from time to time, some of the longer time bitcoiners do panic and make decently sized mistakes with some or all of their BTC holdings, yet many times, the longer term bitcoins will not be very likely to be playing around with large portions of their BTC holdings, so if they make mistakes, such mistakes would more likely involve less than majority portions of their BTC holdings rather than more than majority of their BTC holdings.
Sure, there should be more systems in place that contribute towards longer time bitcoiners to figure out how to manage their bitcoin portfolio and other parts of their cashflow, yet I think that from time to time, some of the longer time bitcoiners do panic and make decently sized mistakes with some or all of their BTC holdings, yet many times, the longer term bitcoins will not be very likely to be playing around with large portions of their BTC holdings, so if they make mistakes, such mistakes would more likely involve less than majority portions of their BTC holdings rather than more than majority of their BTC holdings.
I believe the longer a person has been HODLing, and the lower his/her average purchasing price - he/she would have less probability to panic. That's perhaps because of simple human psychology and experience?
Think of person who bought his/her Bitcoins last cycle with an average purchasing price of $5,000 vs. a person who bought his/her Bitcoins this cycle with an average price of $50,000.
The solution for people who panic - Cold Storage in an offline computer. It will take a few extra steps to move your Bitcoin, making you not to move them at all.
Even if we have long experience dealing with bitcoin still we cannot erase those feeling to get worried about the future especially if we sudden huge dumps just like what happen lately. But the advantage is we could just shove of those negative feelings and could able to continue without getting affected of other peoples fear.
But I guess the purchasing power still the same or increased since right now we can use big funds to acquire bitcoin we already earned some profits compare before which somehow struggling to grab funds to spend on investment. Maybe the only one decrease is the volume since before bitcoin price is so cheap and we can accumulate lots of volume even if we spend less compare to now that we need to spend a lot of money just to get the whole bitcoin. But that's fine since this is part of development as long as we continue to accumulate and for sure profit still there.
Your solution suggested to not get panic in those situation is good, but also they can add this option where they should delete the apps that tracks their portfolio also the price of bitcoin since without getting any further news for sure they will be fine and can think about other things that can divert their attentions.