Removing actual exploits should be a desired outcome for improving the game.
Assuming that it should read "a reasonable ask", while combat with AI may be a cornerstone of the game for those who choose to engage in combat, engaging in combat is only a required part of two of the five in-game paths to Elite. Noting that NPCs are already at a level where they are capable of sending some players to the rebuy screen, and that while Powerplay may, like the rest of the game, offer opportunities for PvP it does not in any way require players who engage in the feature to engage in PvP.
Players can only set the local difficulty of the game for those players who choose to instance with them. Noting that Frontier have already tweaked the NPC challenge once of Powerplay 2.0 based on feedback, presumably to better position it for the player-base in general rather than just the skilled players interested in combat.
If they're in modes other than Open how are they observed to be counted?
Yes they would, but how do you remove such an exploit? Its something that many games I have played have struggled with in the past, and with the exception of upping the capabilities of the enemy they are farming, none ever really take, as workarounds tend to be found by those wishing to continue with them.
Regardless of whether you like it or not, (and to be clear I'm not be facitious), combat is a core part of the Elite experience which everyone is going to experience at some point, unless you literally plot a route straight out of the bubble 500ly (I believe thats still the AI spawn cutoff limit) and never go back within the limits of that spawn. How that player chooses to engage with that Combat opportunity (e.g. run or fight) is a moot point. Its still happening, or at the very least the game is encouraging it (e.g. interdictions). Also, as a sidebar, I think you'll find its 3 'of the game paths to Elite' that require combat.
Regarding the PP2.0 tweak, I wouldn't call tweaking the AI of PP2.0 based on the views of a 'chosen few' who seemed irked the AI might attack them while they are holding court on their twitch/youtube streams a better position for the playerbase. Particularly when you read how folk who don't claim to be steely-eyed combat veterans are finding the AI in its current form as weak, lacklusre and unchallenging.
As has been explained a few times to you by Rubbernuke in the posts you've exchanged over the past year plus, the continued prevalence of the Shieldess Trader in the aforementioned playstyles is noticeable by being (in my case) being engaged with some of the groups and communities of Elite where such discussing such activities boiled down to that being the guidance passed by those running said groups (which is also why I stopped being involved in such activities as a player), including a 'if you dont conform, you have to leave' mentality, screenshots being put out, or simply 'in-passing' conversation.