In my experience, there has never been a season as you said, bitcoin will always be the first coin to increase in price and drag the entire altcoin market up with it. Bitcoin is like the soul of the crypto industry, and everything only works well when bitcoin works well.
That's a fact we all have to admit that Bitcoin is the king of crypto market and will always control it. With introduction of Bitcoin ETF more money is going towards Bitcoin. One main reason why investors are not investing in alts is because their are too many of them and investors are confused on which alt to choose. Moreover their were lots of alts in the past that proved to be a scam and that has also shattered investors trust towards Alts.