Personally, because of the state of the financial system, I cannot see how crypto can become bullish as long as the world economy doesn't show signs of a recovery . I could be wrong though ?
In the midst of the coronavirus epidemic in 2020 when world financial sectors were in shambles, crippled by the lockdown, Bitcoin showed strength. So, to that effect, your assertion isn't right. We often see the stocks market crash but Bitcoin remains resolute.
About knowing when the market has bottomed out, that will be a hard thing to accurately get. This is a speculative market. Even with compasses in the form of indicators, we still can't get it absolutely right. However, I try to look at weekly and monthly close of candlesticks to gauge where the market direction could be on the long term. If a dip has lingered for a while, I begin to expect that a reversal is imminent and I start looking for a possible candle formation to support my suspicion. Otherwise, it's better to do a DCA on a crypto you know will do well and not totally wait for a bottom. There is nothing like a bottom while the market is still in progress. We only get to know that after it has passed that phase.