There is barley any LPS because of it's terrible color rendering, it's rare because of that
In my eyes, it seems like they want to SLOWLY take away lamps with a CRI less than 50 or 60 (MH, HPS, MV, Coated MV)
While on the other side of the world, The UK doesn't seem to care about CRI (I don't know much about UK so hopefully someone will fill or correct) becase they have a large majority of the place LPS (This goes for most European places too)
Why is the US so picky about CRI
Discussions?

I don't think it was even a CRI thing ... HPS has bad CRI too, and its very common here (and MV certainly didn't have a good CRI either).

As to why SOX wasn't more common here, I don't know .. it could be something as simple as the US factories only were making HPS lamps, and UK factories were making both SOX & HPS.

---
Higher CRI (for outdoor/street lighting) is something new that came along with LEDs

The SOX has  a ton of other disadvantages, the CRI is the least problematic of them.
The main issue is the cost: The LPS is technically very challenging technology to fabricate, what means the lamps are very expensive. And the US is very picky about the costs. The real ones, including all components, so the lamp cost, the electricity, but as well the maintenance (here the fact how common is a technology affectsbthe real maintenance cost to very big extent), all summed up. And they tend to compare the cost with real performance. So e.g. not only what the "official" performande ratings are (the brutt lm/W published in lamp catalogues), but what power is needed for a given task, all that compared to what it will cost. And thee thenlarge physical size means the system (quite expensive because of SOX) wold have very high light losses, comparable to (extremely cheap) yard blaster like fixtures.
So with that

The strange reasoning (political factors having higher power than economical/technical ones) I see more on the UK (and generally European) side. The big factor is the lights in the US use to be run by private companies, paid on providing illumination service to the public entities (cities,...). So the city pays for lighting service (that includes certain asthetic aspects on some places as well), but the tecnology selection and all individual costs like installation, electricity and maintenance is on the supplier. So he is motivated to do all the calculations correctly.
On the other hand in Europe the lights are operated by the city organization, where the motivation to really optimize the installation is very low. The public questions are then shot out by waving "standardized ratings" and "scientifically accurate tests" (where the LPS shows excellent efficacy), because these tend to ignore a ton ot real life factors (hard to control to a "scientific standard", but at the end very significant, like the poor optical control attainable in LPS fixtures).
Part of the reasons why the LPS are used in coastal Europe and not US is the foggy weather, which on some places makes the monochromatic lights way superior to provide visibility. Such weather is way less common in the US than in coastal Europe. But even when this is the real technical argument for the use of LPS, it is valid on way fewer places than the LPS use to be installed. Very often this argument was used to defend the LPS installations, for most places it was completelly irrelevant. I'm talking about the history, the officials BSing the people to simplify own work is nothing new on this planet.

I don't understand the obsession with high CRI either. It bugs me the worst with fluorescent tubes. Too many good tubes are gone because they don't have adequate CRI.

IIRC Califonia just banned LED bulbs that don't have a CRI of 90 or more.

IIRC Califonia just banned LED bulbs that don't have a CRI of 90 or more.

That ban is just a BS, mainly with LEDs. It means about 20% lower efficacy compare to CRI80 (still considered good enough for vast majority of home use). And more than 50% higher power for the same light output for low demand uses where CRI60 would be good enough.
It is especially nonsense for LEDs, because LED is a technology, which allows very good application performance gains from the color quality vs efficacy optimizations. With such regulation they just banned the use of one of the main possibility of the technology to reduce their environmental impact.

I may understand the limits on blue radiation for outdoor use, but even that regulation should not be linked to any technology, it should be valid for all (the nature dont care where the light pollution comes from, important it is just its level)

Well, environmentalists in action, what to say more...