BTC is a trusted cryptocurrency and certainly worth investing in today with so much popularity and investment over time. Matching or investment advice with other shitcoins is not correct. There will be volatility in the market and it is advisable to consider trading in the meantime especially in BTC. You said yourself that most coins are dumping but you can check the BTC market chart. BTC is more prone to pumping than dumping.
However you can focus more on managing DCA during dumping period as this strategy will give you the opportunity to deposit BTC monthly or weekly regardless of your income which can strengthen your profit target for the future. This strategy is particularly suitable for long-term investments that maintain a consistent accumulation habit. Reduces even higher value buying. For the long term horizon it is recommended that you keep a floating cash arrangement as you may need emergency funds at any time and your extra cash can help you at that time. he advantage of having float money in case of emergency is that there is no disruption in the investment. You can easily extend your investment and holding for a longer period of time.