~
You made a very good point here but you have to agree that majority of the existing coins and tokens are compatible with safe and secure wallets, it can be a mobile wallet, paper wallet or hardware wallet
In the case of desktop wallets i will also be wary of new projects that appear out of nowhere and only require you to install their desktop wallet
You'd be surprised how many of the altcoins have shady or at least buggy terrible wallets, even the popular ones. For example a couple of years ago someone figured that the official ethereum wallet's multi signature wallet allowed them to steal people's coins very easily.
Not to mention the numerous closed source wallets, mostly for mobiles, that have gained popularity and people
think they are "safe" just because they don't understand what safety means.
About the pump and dump nature of altcoins, i think this depends on your investment strategy, i personally prefer long term investments so i keep my coins and tokens in my wallet to be safe
It does depend on your investment strategy, you shouldn't "invest" in a pump and dump. For example all the altcoins have been losing value against bitcoin for the past 4 years without exceptions. That means they are not viable long term investment options.