Why you shouldn’t take profit is:
1. Using the money to actually spend it on unnecessary luxuries (emphasis on unnecessary, as there is nothing bad to get some luxury for your self).
2. It is wrong to take profit and abandon it on fiat currency, that’s going from an asset with a store of value to one with devaluing characteristics.
3. Taking profit to actually invest into altcoins because there is predicted alt season coming with some Altcoins been rumored to be able to do 5x or more is a capital gambling which mostly results more into losses than profits.
4. lastly Buying Altcoins are not diversification means so do not take profit from bitcoin to buy Altcoins.
Your point number 3 and 4 are a little similar as to selling bitcoins to buy altcoins. May be you should consider combining them.
This is the exact mistake I have made in this bull cycle and I obviously regret making this choice.
I have learnt my lesson though and won't repeat this mistake again. Holding my bitcoin stronger now.