This feels like a question for me - so let's talk about the difference in some more detail.
Hacking opens up new subversion possibilities. Right now you could, as a subversion action, attempt to hack the mechanicus nukes or orbital satellites. There would be a roll, and how well you rolled would determine the outcome - all the way from "Now the mechanicus knows somebody tried to hack them" to "You can change the targets/orders of the satellites." Getting better tech will improve the outcomes on that - change the probability distribution of the roll, and let you do things like target all of the satellites instead of just the ones that pass over your base.
Jamming is a combat-oriented solution. Once you research the tech you can create "jamming modules" as installations or ship weapons whose purpose is to bombard the satellites (or any other target you can link them to) with signals designed to confuse their machine spirits. It won't totally neuter them but it will slow them down and make them less effective. A combination of some jammers, a shield and either fighters or some anti-orbital lances would be a good way to protect yourself against the mechanicus weapons. But on their own the jammers are not a good solution to protecting the entire planet. The jamming may also serve as a good personal tool in actions, but it won't be as significant for that as the hacking will be.
Hmmm. This has me convinced that hacking is more urgent to get, because we likely shouldn't try to get everything perfect. If we can afford only one branch of the hacking/jamming tree, hacking is the one we should probably take as far as we can. Changing my initial plan-draft to fit this in my new plan, jamming replaced by faster hacking.
[X] Plan: We Make Manufactories To Make Manufactories
-[X] [Free] Poke around some more in the databases, looking for anything in particular.
--[X] You are morbidly curious about what has happened to the Eldar. By the time humanity had reached beyond Sol the first time, the Eldar Dominion was already
the unshakable titan amongst the stars. Had been, according to what they told, for millions of years. And was so still by the time of your accident. What happened to them? Wait, what is this mention about "the Dark Eldar" in your self-censored notes about the sealed Mechanicus files linked to --MAJOR_COGNITOHAZARD_WARP_ENTITY_4--? You had quickly skimmed over the part as not urgently relevant at the time. Sigh. You can already feel your shielding starting to fray a bit again just when thinking about it. Literally. (Learn what you can about the current state of the Eldar, and also sacrifice a (hopefully) small amount of psychic shielding to learn about the Dark Eldar and their link to Slaanesh.)
-[X] Diplomacy (Admech):
--[X] Time to construct yet another false report, yay. Thank the stars for your diplomacy and reality-simulation modules. Without those, you would be worried about the report potentially showing inconsistencies. Give just enough to satisfy Thalya, but not to raise her hopes further. Also, continue subverting those interested in your puzzles and lessons, and see if you can maybe widen the net.
-[X] Construction (1100 BP)
--[X] Construction slot, 1st
---[X] 10x Manufactories (100 BP, 50 CP)
---[X] Shield Repair (50 BP)
---[X] Trade Goods, Aevon (50 BP) (stored 20 -> 70)
-[X] Research x2 (400 RP + 10 Anexa RP)
--[X] Research slot, 1st
---[X] Blueprint: 100 RP - Medium Void-shield installation (1000 BP, 50 CP)
---[X] Small-craft Stealth (100 RP)
--[X] Research slot, 2nd
---[X] Faster Hacking (150 RP)
---[X] Brain Implants (40 + 10 Anexa RP)
---[X] Blueprint: 10/15 RP - Anti-personnel Bunker (20 BP, 2 CP)
-[X] Pay rent (Trade Goods, Aevon 70 -> 55)
-[X] Anexa active Action: Research (Brain Implants) - assists a research action you take, granting +5xLevel RP to the action. Will level on successful roll, scaled by the importance of the tech.
--[X] [Free] Write-in: Warn Anexa that you just found that the Mechanicus and the Imperium were right about there being a "corruption" that you both will have to be careful about. Because it is a literal warp-based cognitohazard, particularly dangerous to the AI, but even resistant beings with "souls" like humans and machine spirits can be corrupted. Your shielding took a hit even with all the precautions you set in place, though fortunately it caused only minor fraying and nothing got through, it seems. Tell her that you are hoping to miniaturize your shielding fit for human sizes at some point, thought this is currently far off in the future. Especially important if she is interested in the topic, even in how to combat it. Because you had to seal the information regarding this topic into a memory vault
. Just to stop your shield from continuously fraying from stray thoughts regarding it. Meaning that even during this conversation, you don't know more than the surface details for the very rough warning signs. You ask Anexa to promise to tell you if you or your tech starts to act weirdly, because it might save both of you if it comes to it.