In the current crypto market, the value of Bitcoin is compared with the value of AltCoin. It is never possible to get that much profit by investing in altcoins, most of the altcoins are scams. However, by investing in Bitcoins one can avoid facing losses. If the Bitcoin market is down, it will surely rise again. So Bitcoin has the most investments compared to altcoins among the current cryptocurrencies and the future of Bitcoin is the brightest.
What you said about bitcoin is correct. Bitcoin may fall to a large percentage but we are sure it will rise again. This cannot be said about alcoins, some of them may not see their previous ATH let alone to see a new ATH. But whatever happens to bitcoin there's a guarantee that a new ATH would be seen