There are some physical similarities to Robber Baron on "Loki" and Alton Osborn Sr. from the comics. The most prominent is the inclusion of mutton chops connecting via the mustache. This must've been a popular facial hair style toward the end of the 19th century. But if one really wants to dive into this random cameo, Robber Baron's presence may explain why we haven't met Harry and Norman Osborn yet in the MCU.
In the comics, Alton's grandson, Amberson Osborn, lost the family fortune after an invention he made with unknown uses was stolen. While we don't see Amberson in "Loki," Robber Baron makes a very unfortunate business decision by investing a ton of money into the Temporal Loom prototype, which turns out to be a scam. It's possible he also lost much of his fortune through that transaction, forcing the Osborn family to work their way back up. It could explain why the MCU doesn't have Oscorp yet; it's possible the Osborns may be fairly wealthy in the modern day, just not to the level people are used to seeing them.
It's a long shot and probably isn't accurate, but that's the fun of making fan theories. "Loki" has incorporated many deep-cut Marvel Easter eggs into Season 2 already, from a movie about Zaniac to a reference to Balder the Brave. There's a rich web of Marvel history at play that only the most devoted of fans would pick up on.
