That's a key to understanding the relationships. Tom yells at Sonny, Sonny yells at Tom, but it's more like two brothers fighting, and Sonny as you note immediately feels bad and warmly invites Tom to dinner, and says "Mama" made dinner, not "My mother made dinner." You can tell he's genuinely remorseful for snapping at Tom and knows he hurt his feelings. Sonny may have been a bad Don but he was a human being.

Michael didn't seem to have a single bone of love in his body for Tom. To Michael, Tom was Sonny's friend who Vito adopted who was useful. Beyond that, he was a weak and contemptible man given to whoring, a useless Consigliere, but a good lawyer who was useful and whose need to feel truly part of the Family could be exploited. That's it. He was utterly willing to cut Tom out of his life fully and permanently for even contemplating a job offer, and humiliated him as a man in front of people who are on paper subordinate to him. He had little use for Tom beyond what Tom was useful for.