Its not a serious issue but its serious enough to affect his professional relationship with others. Dive producers who he actually have had good relationship with before is also taking offense and siding with Jamie. Even the merch brand he worked with, represent, they had already unfollowed him on IG. While the main mass audience may forget, its already recorded in many professional companies and production that this guy is problematic and can bring harm to their brand.
I think that this was the final straw for them since it seems that they are very quick to drop him and seeing how he acted last year, it’s most likely not the first time that he disrespected someone close to him (whether it was publicly or not)