Anytime the price of bitcoin is also not growing including ethereum and litecoin but if most other coins are growing, it is still altcoin season.
No. Altcoin season is estimated by the trend of the top 50 altcoin (mainly 75% of the 2nd-50th ranked altcoin) on the market capital so altcoin season cant be calculated by the exclusion of all the two coins you listed and the uptrend have to last atleast 90days but the market trend is not decided by Bitcoin price momentum (cause the investors will only focus on altcoin as investment).
Which means at the time, Bitcoin will not grow while many other altcoins are growing.
Absolutely.
I don’t understand what an alt season is other than altcoins growing in price. Why do they grow in price? How do people determine whether an alt season has begun?
Read the above messages and youll have an adequate awareness.