This is true there are allot of crypto projects that has no future value and prospects so investing in such crypto projects will amount to lose and this is what Many has experience especially with altcoins so prioritizing investment in Bitcoin with a good future prospects and investment value will be a good one as investments in Bitcoin safe and secured
What people don't understand is that you can not compare Bitcoin with those projects. Even if the price of Bitcoin is going up, there is a very high possibility that the price might not go up. This is all part of the reason people are always advised to invest in Bitcoin because it is the one driving the market. When you invest in Bitcoin, there is a higher chance of winning. It is better to go for the one that is winning.
There are other coins that aren't a bad idea, but at some point, you can strategize your own way of investing so you can do both bitcoin and altcoin, so we just need to know how to make useful of the information we have.