Bearish is indeed the best time to buy but sometimes buying on a bullish market is still good if it's a confirmation for a reversal. Yeah it's very easy to say that it's good to buy on bearish but how long will the bearish occur before the market finally recover to take some profit.
A pumping market after a long bearish trend is one of the time to pruchase Bitcoin if you want to have a high chance to purchased when the market is recovering instead of dumping to maximize profit because you can purchase on way higher if you just buy randomly on dumping market. Atleast on confirmation buy, You have a high chance that the market will go on bullish right after you enter.
It basically depends on your financial goals and personal choices whether you want to buy when the market is in a bear run or you want to fill your bags when the price is about to start the adrenaline rush, if you are a long-term investor, you should probably buy when the market is in a bear run because you will get much better prices, but, if you are just a short-term investor and want a few percentages of profit, you should definitely trade only when the market is in a bull run.
When you buy right after a bull run has started, you will have enough time to just sell when your target has reached or you can keep holding more if the price keeps going up without any stops because that will obviously generate more profits for you as a short-term trader.