It wouldn't really help. There's (post-Thargoids, and allowing for exclusions like permit systems, etc.) a bit under 20,000 systems in the bubble.
A little over 17,800 of them have at least one PMF present, so couldn't be used to add a new one even if it was still working.
So ... how do you tell that a PMF is dead and can be removed? Most of the suggestions I've seen are along the lines of "if it's been retreated to just its home system and is on really low influence in that for at least a week" ... which would catch virtually none of them; random passing traffic keeps a dead PMF more alive than that in most of the bubble, so long as it isn't Anarchy government.
If you consider a really harsh (i.e. will get a whole bunch of false positives) method: any PMF which doesn't currently control at least one system ... then this frees up just 600 more systems (and probably fewer if the false positives are removed). There are more dead PMFs than that ... but their systems have already been expanded into by other alive and aggressive PMFs - just the top 50 PMFs between them were blocking almost a quarter of the bubble (and rising) ... and if there was a published rule for "dead" it would of course be in the interests of nearby active PMFs to ensure that none of their neighbours ever quite met it until they'd managed to expand into that system themselves.
I think we started mentioning "space for PMFs is running out, something might need to be done about that" about four years ago - without any workable ideas for what, though; if it hadn't been for the post-Odyssey slowdown, then it would probably have already run out on the earlier trend. If they hadn't accidentally broken it when doing something else then this day was coming soon anyway. Which is no consolation if you would have got in before the cutoff otherwise, I know.
That's true, though "BGS" is more of a why than a how. I trade, bounty hunt, run missions, explore, etc. Telling my actions (which aren't at this time aimed at getting any particular BGS outcome) apart from those of a dedicated faction supporter would take a fair bit of looking at the details.
That PMFs are popular is kind of the problem; if they weren't, there'd still be plenty of space for new ones and it'd be more worth Frontier's time to fix the process for adding them.
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