It’s not totally baseless assertions though. Yes, there’s the YouTube experts, the FIFA experts, the scouting from FM experts and they all have at least some value. How little value is subjective. What you can do is take up what you’ve gathered, take into account what others who know more about the player have said, do your own research, trust that the staff has done its due dilligence and then make your own subjective opinions and speculations.
I’ll give you Gabriel jesus for example...dream signing for me. I sought out info, discussed via PM opinions on him here with posters who watch the Brazilian League and who I respect and then started watching a few palmerias games, the Olympics, etc. We happened to sign him and I would have started him over Kun from day one...that’s how confident I was and he’s turned out just as well as I imagined...maybe even a little worse. Still think he has a lot to show. All of this simply because I heard he was a phenom on football manager back in 2015 and started watching clips.
In the case of Lucas Paqueta it could be much the same. The same posters I respect and who watch every flamengo game have said he’s the real deal. you combine everything you know and if the club is after him then you can be sure he’ll have a great chance at living up to expectations.