I won't be surprised if PAF adopts FC-31/J-35 in future. But I think the key point is time. 2025 and 2030s are quite different. I am assuming the early batchs would be carrier-based ones, PLAAF versions would be later. I think PAF may wait for a while until the birds are mature in PLAAF, just like J-10C.
On the other hand, I doubt if China is willing to export those stealth jets to Pakistan when India doesn't have any. Actively upgrading an arm race has never been a part of China's foreign policies. Considering India has no way getting any stealth jets Su-57/F-35 before 2025, I expect PAF to get their first FC-31/J-35 in 2030s.
You know from Pakistani POV I agree with you
Arms race shouldn't escalate where India requires a 5th gen fighter
But what the ideal/prefect situation would be
is
A- decent option against Rafaele (which J-10C is, it hopefully finger's crossed won't be routed by Rafaele)
B- Some PAF pilots be trained on FC-31 so if war erupts we can get these fighters on an emergency basis
Or if it's close to happening and India is bullying
we can get a small batch to just serve as a deterance
But don't think we should get 5th out of nowhere