Hmm, I don't think that checks out from my experience. You can basically ignore hostile activity and a colony can do fine; even the highest level penalties aren't that bad.
What kind of monthly points gain are you seeing? There's one likely raid at 75 points and it's non-repeatable, and after that building up to 500 points takes a while. You're unlikely to have more than... not an exact number, but like +15/20 per month from pirates alone? So you're looking at over 1.5 cycles between raids at worst, and killing a few fleets now and again sets it back a lot. And the bonus from increased defenses/a military base is going to drag this time out *a lot*, possibly stalling it out completely. This just doesn't add up; you're not going to be seeing pirate raids all that often unless there's a bug.
And there are options for dealing with each of the hostile activity factors individually; the tooltips offer some information as to how you might do that.
I mean, if you install a ton of AI cores and event progress ramps up more quickly because of that, then yeah - but then that would be entirely on you, right? And at worst the core bonuses should more than cancel out the penalties from high hostile activity levels.
I'd love to see what you're actually seeing; this doesn't make a lot of sense to me and it's possible there may be a bug somewhere.
I think most of what's happening is that previous patches made 10 stability and enough access to export everything and then some the default, and the idea that sacrificing some of that might be needed in some cases is causing some players (myself included, admittedly) some issues with prior expectations vs new (ultimately perhaps intended) mechanics. It caused me some stress until I spent some time thinking on it, and then went on with my own chosen methods for mitigation.
A totally new player with no preconceptions on how to build and manage colonies might have it easier. I don't know. My experience definitely worked against me at the start since I gathered enough resources to juice my colonies up and spread some items out.
What I can say is that the progressive stability and access debuff hurts in the latter two stages, out of proportion in credit cost (considering what less stability and access does to credit income) with the actual problems caused with the recurring event. Pirate raids are anemic in the face of how colonies are expected to be spawning space patrols against faction expeditions, and Pather cells are solvable. The debuffs hurt especially much if you've got just enough to slowly tick up threat and not quickly get yourself through the higher penalties. Which a player probably does if they've spent time exploring.
I think there's some room for additional stuff at the conclusion of the meter to bring it into proportion with the debuffs, or maybe the market value of goods need a little buff since 10 stability isn't a baseline for most of the game if you're putting items and whatnot in anymore, or perhaps some more events in the meter to switch things up. I don't know. I can say that it felt bad when I was just starting up my colonies and didn't know how to game the increased threat, but after learning the mechanics it's entirely manageable.