So sorry to hear that. But as your experience, not all projects are valuable and survive to have a brighter future. Many are shit projects or scam projects. That is why I personally always avoid new projects, moreover that have not been listed in any exchanges or listed on DEX or low cap exchanges that only utilize the pump and dump process. this is high risk.
It is true also that we need to diversify our money into several coins investment. But it doesn't mean that we must invest in numerous shit coins.
It is better to invest in Bitcoin at first, and top coins. At least, we can decrease the risks. However those top coins are also valuable for long-term investment, althoguh right now the price still decreasing, but I beleive that this will be able to rise up in the future.