Yes, it's speculation, but it's informed speculation. Guys in the same recruiting classes or recruited by the same coach are going to bond with each other, especially if they are in the same in the position group. Spielman is one of the few players left from the 2015-17 classes, especially as an offensive skill player. Players go through a lot in their transition to college. If there aren't many players left from those classes, the remaining players can struggle with finding a place with the recruits coming in. This is probably especially true with JD because he seems like a quiet guy, who won't speak with the media, so he it's possible that he's not interested in befriending and being a vocal leader to the younger guys.
It's similar to being in a fraternity where most guys are friends with guys in their pledge class and a year above and below them. By the time someone is a senior in the house, a lot of them don't really care about getting to know the incoming freshmen as close friends. They are in different stages of their college lives.
There are comments about Spielman working out with Tyjon Lindsay in Omaha this week. So, Spielman is choosing to work out with a guy who hasn't been at NU in nearly 2 years. Spielman is probably a lot closer to Lindsay than he is with any of the current receivers on the team. The only receiver that I would think Spielman is close with is Kade Warner because they are both "Riley guys" and their dad's ties to the NFL.