Bitcoin Dominance (BTC.D) increasing means the altcoin portfolio is definitely suffering.
But have you noticed that for the past 1-2 months, BTC.D has clearly decreased by over 5% from its peak (a 5% drop is quite significant, not negligible at all), yet the altcoin portfolio still continues to shrink, how is that possible?
So when we say BTC.D decreases -> altcoins increase, what does that mean?.
In fact, it's true that when BTC.D decreases, altcoins increase, but specifically it means an increase in market capitalization, not an increase in price.
Looking at new projects and token vesting of that size, how can prices possibly increase?
In summary: $BTC and $ETH remain the best, safest, and most sustainable choices.
If we are currently in a downtrend, BTC and ETH can absolutely hold + DCA for another 4 years, but getting involved with altcoins during a downtrend is likely to lead to losses.