SJs perhaps seem less intellectually curious to you than NTs because we are systematic thinkers. We don't challenge your ideas or do the sparring back-and-forth like NTs do. That doesn't necessarily mean that we're less intellectually curious, capable, or intelligent than NTs. SJs tend to think "inside the box" and accept things as they are, incorporating ideas into universal belief systems, rather than challenge mainstream ideas and look for hidden meanings and connections.
So maybe it seems like we're not intellectually curious, but we're just not interested in testing ideas with you or engaging in debates or sparring. I'm not a confrontational person, so if someone tries to provoke me, I'm going to give my (differing) opinion, but I'm not interested in arguing with you. When I get attacked by people I tend to ask them questions about why they believe what they belive, rather than challenge their position. This is IRL face-to-face conversations - in writing, I will tear you apart. But I'm a really curious person who is more 5ish than SJ. I want to know about everything and anything.