I don't often give advice as to others swing, I usually am looking for it, but....
That swing looks like my son's through most of HS and I didn't like it. The thing was he was pretty successful with it so getting him to change was difficult. Anyway, notice the head of the bat drops almost straight down parallel to back shoulder and arm. The path is more an L shape than a C. I can't see on my phone but I'd bet the rear elbow is getting in front of the hands causing bat drag. The other problem with that is while the bat head is dropping no real power is being produced. Like I said my kid did the same thing. It took a crappy sr season for him to agree to change. Given the PO his freshman year and limited time in summer ball it's taken a while to judge results but after a slight adjustment to his approach at the plate he's doing pretty damn well last fall to now. Maybe others will disagree and that swing did get him a DI scholarship but thank god for that sr year. That's my .02.