It has not been nerfed in ways that make its abusability unfeasible. Reducing the yield only means that you bring more Rorquals, which is exactly what happened after every Rorqual nerf. One could even say, CCP nerfed the Rorqual in ways to line their coffers instead of fixing the economy because they intentionally banked on people creating more Rorqual alts to compensate the yield nerfs with more skill injectors and plexed accounts.
It’s a sitting duck that can make your entire miner swarm invulnerable for a period of time to allow your super umbrella to respond, and it dishes out considerable DPS while being able to repair considerable DPS.
Thus, the Rorqual has not been nerfed in any way to make its abusability unfeasible. To fix the Rorqual, the activation of the Indu Core needs to be limited to one per 1000km around a resources containing object. In addition, every single feature it offers can only be used or be effective with the active Indu Core. No PANIC, no excavator yield, no tank, no compression without the Indu Core. As compensation, you could revert all the yield and some tank nerfs and give it even better mining boost levels. That would lead to Rorqual swarms to be effectively dead and you’d have to be very good at chain PANICking and people would have to use exhumers and barges again to mine, which are much more cumbersome to multibox and much more vulnerable to attacks or booshing.
It would lead to more of this: https://zkillboard.com/related/30004733/201811102100/ instead of having to bring dozens and dozens of chars to break a Rorq tank. It would also require more tactical decisions from the Rorqual pilots in case of attacks: Do you save your mining fleet with the PANIC and risk the dread drop killing you later, or do you let your mining fleet die and save the PANIC for the escalation?
Overall, abuse of the Rorqual culled, it would be returned to its original role as ultimate mining support instead of being the ultimate mining ship that obsoletes every other mining ship and its use would require actual tactical decisions and not the crap that CCP calls tactical decisions.
That point is completely irrelevant to the matter. The Rorqual is not the best ship for its activity, it is the only logical choice without any meaningful drawbacks. The price or the amount of skill training are not a drawback at all in an environment that can hand these ships out like candybars and give people Skill Injectors to get the alts up to speed.
Why? See, this is the problem with uninformed people like you who can only sperg nonsense just like CCP does. Hulks are much less convenient to use compared to Rorquals. Their ore holds are tiny and it needs to be emptied every 2 minutes into a hauler or Rorqual. Plus, they are incredibly fragile and therefore are very engageable. A swarm of them can surely be a menace with all the drones, more so a Swarm of Skiffs, but even they are much easier to attack than a swarm of Rorquals. Before you sperg this kind of nonsense, please at least try to inform yourself a bit to make yourself look less like a fool of the likes of CCP.