The past bear market showed that alcoins are falling in price more faster than bitcoin (and even the strongest of them is Ethereum). Therefore, as soon as the market falls, it is necessary to withdraw assets, well, or transfer everything to bitcoin.
you mean to say transfer every thing to Stable coin once the Bear market starts including Bitcoin. We don't want to put your money into some thing that will also loss its monetary value even though you think it will be going more gradually that the alts. I do believe we still have some time for this to happen though hopefully still some time in the fourth quarter 2021.
I would say if your money and altcoins are on exchanges and you want to do what you just said, best way to do it would be to put stop loss and that way you would be actually doing quite good without any problem and still be ready when a bear run comes.
How? Your money will be in the exchanges which means it will be easy to sell it and if you do put a stop loss that means you will be capable of actually selling when it goes down even if you are asleep at the same time, that is very important because bitcoin and all of crypto is acting very fastly without really caring about what is going on and if you are asleep or outside or anything that makes you busy, which is why I think it is quite important that you put stop loss just in case bear comes when you are busy. This will make sure everything you asked for and you will be capable of doing it without doing anything.