A cat that’s fucking bored and trying to bait you into wrestling/playing with it (because most cats don’t quite get humans aren’t other, larger, more clumsy cats) and a cat that’s fucking terrified of you and just trying to defend itself from something it believes is threatening it are two very different things. If Jasper was actually afraid of Phil it’d be very easy to see and if it did manage to bite Phil I can promise you we would never see or hear from Jasper again because Phil would do something certainly drastic and possibly cruel. Also cats aren’t stupid (okay, they are, but not in this way in particular); if they’re afraid of someone they cohabitate with they’ll avoid them like the plague. Cats are domesticated but they’re not possessed of the same desire to please dogs are. They won’t try to bridge a gap like that on their own, they’ll just run from the person or hiss and growl if they’re cornered.
Phil could actually encourage play with Jasper if he had a variety of toys he could use to interact with him, or if he just wasn’t a pussy and used his hand to wrestle with him, though granted some cats don’t know how to play any way but rough so I’ll give him the benefit of the doubt there, but I’ve also never seen Phil play with him using anything other than a stupid pipe cleaner toy or something on a string, and cats need way more than that.