I suppose that is one way to sort out the 'rise to power' games
It is a grave concern that such crippling bugs came out of nowhere. Going from several reddits a number of players have shelved PP and the game itself while this is sorted out, leaving the whole thing hanging.
But since we are the smallest powers, who cares?
Most of our passive bonuses, which were half working, have also stopped. Narcotics and Battle Weapons have been removed from most of our Control Systems.
To answer the OP, things certainly have changed.
I'm Elite in combat (which means I've grinded away at our expansions, it hardly is an indication of skill) and I have very large bounties.
When I arrived at systems, I would be interdicted by an Elite bounty hunter (even the eagles are a pain).
If I interdicted a PP ship to undermine, the Elite bounty hunter would instantly drop in and open fire on me.
Fighting these ships in my Imperial Courier was the most fun I've had in elite dangerous since PP started.
The fighting with Elite NPCs is very similar to the good 1v1 PvP fights I used to have in my Viper, before PP brought nothing but 4v1 seal clubbing (I've been on the 4 end more than the 1 and both are as pointless as each other)
But, from a power play perspective, I feel horribly disadvantaged, to now have to deal with elite bounty hunters while undermining/expanding, while the vast majority of players are not experiencing this.
So I'm split, earning merits was much harder for me, but the game is more fun.
The bounty hunters have left me alone now, because they finally killed me.
But if I go undermining, they will return.
Again, I don't mind them trying to kill me again, but it will drastically cut into my undermining merits.
The OP mentioned the increased security response (40 seconds in high security is what I've been seeing) which has basically stopped undermining this week, Delaine hasn't even got 1 system 100% undermining at this point in time.
Here's the laziest way to fix a decrease in undermining, increase the amount of goods needed to fortify.
Increase fortification triggers by 5x to 10x and that will re-balance it.