It's possible, but if you didn't follow him every day to witness this, then you won't be able to tell.
I'm following one guy on Twitter who turned $1K into $1M in the last 6 months, and I believe he is legit. Thousands of people see his trades and videos every day, and no one's complaining.
I'd also believe it simply because recently there are millions of new traders with a portion of the $2 trillion stimulus to spend, and lots of money is being made (and lost).
I mean, if this wasn't even possible then all of the history of trading would've been false, no one would care for trading, and this forum wouldn't exist. No one would be here if they never heard and believed that any successful traders ever existed. While if they did in the past then there is nothing stopping anyone to be very successful today.
Basically I think it must be possible for exceptional traders to exist, and I can believe some. But I'm not sure whether there is a reason to verify any specific claim. Maybe this guy did it, maybe another one. The odds are one in a million, so you don't stand a chance of repeating this. But you can follow any traders that are consistent and still learn.