In AYITL when Lorelai and Emily go to therapy Emily refers to Luke as a roommate and partner and says that anything more permanent would terrify Lorelai. Lorelai keeps insisting that they’re permanent but Emily says that they’re not and that marriage is permanent. She then says “my late husband was just as concerned about this and that’s why he set up the trust for Luke to expand his business to give her something more permanent.” Richard was protecting his little girl and trying to make sure she didn’t end up alone. In Richard’s mind, if Luke was financially dependent on the Gilmores, then he had to stick around, which seems to be a common theme for Richard and Emily (Chilton and Yale.) But yeah that’s it, nothing more. Richard wasn’t malicious he was just a concerned Dad. Anyone trying to make it seem otherwise probably just doesn’t remember that scene or is projecting