Yeah, I noticed that, too. I wanted to demand the Arceans stop building their military starbase in my territory ... or else! I could demand they give me the starbase, but they took that as a request for tribute. I had no way to communicate my displeasure at their provocation.
I also couldn't convey to them my perception of the intensity of their provocation.
Lots of strategy games have ways to make threats, and most of them allow conditional threats, "Do X or I'll declare war," and a refusal actually puts you in a state of war. The AI "knows" (as much as an AI is capable of knowing things) what the stakes are.
With the GC series and Master of Orion series threats are implied: "We demand tribute of resource X," where X is any of numerous possibilities, is an option both you and an AI opponent can choose, but you can't explicitly tie it to anything negative.
Given how sophisticated GCII's AI is, where it actually "knows" a particular action like building an influence base in the middle of your territory is a casus belli, it should be able to tell the difference between a player demanding tribute versus a player calling shenanigans.
But if you give me a choice between a smart AI with an unsophisticated interface versus a brain-dead AI with a very sophisticated one, I'll choose the former. Emperor of the Fading Suns AI was so bad it couldn't put up a fight the first time I played it, but wow did it have some cool diplomatic options. Yawn.