There isn't resistance to adding harder mission templates, or more challenging USSs & POIs. There is resistance to raising the general existential threat.I don't really get the resistance to adding ultra hard PvE missions above what we have now. Its blind luck stacking to get something sweat inducing, while NPCs work to simplistic rules that are easily identified making them predictable.
Since 2.1 the game has sent rank & ship based NPCs after the player every few instance changes. They are not as irritating as they were (I am triple Elite & no longer interested in combat, having Elite Condas improbably sent after my tasty (salvaged) cargo was what drove me to leave the bubble in 2016 & not return for 18 months) but this is the area where a player could reasonably expect to survive an exciting encounter rather than have to fight for their livelihood. I'd have preferred location based challenge rather than rank & ship based - the whole 'anarchies are dangerous' bit. And they are, sort of. The difference just isn't much, and with report crimes off, there is no difference at all.
The game already provides more PvE challenge for those that want it, more could be done in this area, more could be done in a lot of parts of the game.