Could be a situation where he gets your preference and assumes you wouldn’t want to play a different format. For example. If I have a friend who only plays competitive rules smash bros, then I might not think to see if they want to play casually with items.
To take it one step farther, if I have friends who I know do not like to play a game competitively, I might not invite a friend who does due to the former who made the plans with me not wanting that pressure.
In this last case it isnt a specific value judgement of my competitive friend, just me not thinking my friends with different styles would gel in this instance.
It could also be that he doesn’t feel comfortable adding others to that particular set of plans. Say for instance his buddy is going through something and they are playing the game as something to do while chatting about it.
One way to approach it without sounding needy would be to extend a offer. Simply stating that if people ever want to play at a future time you would be interested. From there you could have a possible avenue to express your desire to participate without coming across as hurt.
This is a long response, but I hope that regardless of how this plays out that you don’t take it too personally if he chooses not to include you in the future. From what it sounds like you two are close and maybe he just likes to keep his social groups separate.
Yeah but JRRT wrote a whole history textbook and invented a language before most fantasy authors were born.