1. Scarce Resources : It was difficult to write on ताड़ पत्र . There was no paper or ink. Acharyas used Taad-patra and thorns to write all these scriptures. Sometimes, the thorn would pierce in their palms and cause blood ejaculation (blood is found at the backside of many taad-patras).
2. Degrading Knowledge Capacity : The grasping and retention capacities of beings is degrading. Acharyas wrote down sufficient matter for all anuyogs and Gyanis made it as simple as possible for us. We will even struggle to comprehend and understand the presently available karnanuyog as it involves high-level mathematics and formulas. Then, writing down rocket-science for us would have been a unfruitful move.
3. Pancham Kaal and its characteristics : It was forecasted that Jainism will be at its knees in pancham kaal. The lower-castes will rule over. People will not have much interest in religious acts/knowledge. In such a time, the acharyas had intention of writing only प्रयोजनभूत and सारभूत material for all of us. The available karnanuyog has ample description of planets/sun/moon and their movements. The explanations on these things would have been endless.
4. Faith Constraints : The available matter on revolution and movement of planets/sun/moon as per Jainism is enough to build a faith in the subject matter of Jainism as a whole. As Pt. Shri Todarmal Ji wrote in Moksha Marg Prakashak ―
“जो प्रयोजनभूत विषय में असत्य नहीं बोलता, वो अप्रयोजनभूत विषय में झूठ क्यों बोलेगा?”
And for once, let’s imagine that Acharyas had written all of the planetary science matter in their granths. Do you sincerely believe that scientists would have agreed on that? There is an on-going debate on Flat-earth and round-earth ― the very basis of rocket-science. The scientists would be asking for conclusive evidences on the matter and our clarifications that - “Because Kevli bhagwaan said so or our Acharyas wrote that” wouldn’t work. They work on facts and not merely on faith.
लौकिक विज्ञान मात्र ज्ञान का विषय है, धर्म श्रद्धा का विषय है
So, there are some problems. We should content ourselves from the available Jinagam (which, by the way, is quite vast) and should focus on our Kalyaan.
Hope this helps.