When gold prices (in dollars) soared from 70s stagflation, then crashed, was it smart to sell the top? OK, how do you know what the top is?
In gold’s extreme, extended bear market, after it started crashing, was it smart to sell at $800? $700? $600? Selling for $600 and later re-buying for $300, you could have doubled your gold holding.
...$500? $300? $260? Whoops! Selling for ~$260 (IIRC*) would have been mindrusting gold.
Holding gold is always safe, if your biggest concern is not to be stuck with less gold than you have already accumulated.
Holding BTC is always safe, if your biggest concern is not to be stuck with less BTC than you have right now.
* Numbers here are tossed off the top of my head to make a point. If someone corrects any errors as Jay corrected my recollection of when Slaying the Bearwhale occurred, then... eh. Here, at least, it will not change my point.
So you are saying investors should only accumulate gold or BTC to increase their portfolio? If you do not extract some profits from your gains and reinvest them in that same assets or something else then you are not an investor. You are more like a collector. Professional investors always circulate their money in the different asset classes. If you do not know what the bottom or upper limits are then follow the market sentiments.
If you think of yourself as an investor you must keep track of the market about what's going on. Many people think a bear market is a downside of our economy but wise investors knows this is their opportunity. You can get things with a high discount price in a bear market so buy when everyone is selling and start selling when everyone is buying. This is that simple if you do not know about price actions charts or fundamental analysis.