For example Suppoman is very hot in Ethos, why? Because he received hundreds of thousands of them back in August.
Suppoman is a known scammer. He got paid from several shitcoins to feature them and even bragged about it.
I'm honestly not even surprised. John McAfee does the same things. Ivan the Tech seems legit though

Most youtubers do the same thing. They promote coins from which team they are paid.
It's very hard to decide who to trust.
Do some research yourself and always trust only yourself. I'm using youtubers only to get notified about new coins

Problem is that by the time it seems many are making videos about a coin the easy money has already been made.
That's the thing, whenever they make any video regarding a coin (usually to pump it), it is one of the signs that you should sell that specific coin. Right now, I'm treating them as alerts for when to sell the coin that they just got promoted. Or, you can hold on selling it and start to monitor the market of that coin for any movement. More often than not, people will start FOMO buying that coin and that will provide you a better exit point. Never ever start buying the coins that they just promoted. They'll just dump their bags on you (bags that they accumulated few weeks ago).
If you take that approach, than there is absolutely no coin you would buy and hold, because there are videos about each and every coin out there.
This is how I do it - I join telegram or discord channel of certain coin and talk to admins/devs.