I remember disliking the trade immensely when they made it, simply because I thought he was an underrated prospect that had a good GCL season when he was 18. Plus he played the infield and had more room to move on the defensive spectrum than say Rixon Wingrove who is the same age but got outhit by Mead in 2019.
That being said, Mead did not have loud tools other than the hit tool. Hopefully we are seeing the value in the hit tool with Lee and NPG who both have kind of similar profiles of infielders who do not project to be great fielders while also don't have huge speed or power. They just hit line drives and know the strike zone really well for their age. Hitters without tools often don't project that well to the upper levels.
The Phillies probably figured he was a longshot and that Cristopher Sanchez was a good bet to be a useful 6th starter type. They at least were right about Sanchez who has been useful depth, though of course it looks like they are very wrong about Mead.