@Lightingeye60, note that the statement you said generally applies to the USA in particular. Me and Baked Bagel 11 did specifically state that other countries still embraced mercury vapor lighting long after the USA phased them out after 2008.
I don’t know that much about other countries but I know other countries have different rules (like in some places, incandescent bulbs are still sold). Same goes for Mercury vapor lights. Both the United States and Canada banned mercury vapor fixtures in 2008 (though I think Canada allowed probe start metal halide, unlike the U.S.).
And, 90s or 2000s mercury vapor fixtures were not too uncommon as spot replacements (they were most often used as spot replacements to replace older MV fixtures), this was a quite common practice to match the old fixture or other fixtures (as HPS wouldn’t clash well with mercury vapor). They also were sometimes installed to replace all older MV cobra heads to modernize the look of the fixtures without changing the look of it at night (which is what using HPS would do). Cities frequently replaced old fixtures with yellowed polycarbonate lenses, that are dayburning, or simply because they wanted a new fixture. Which is why you may see some places with a bunch of 2000s MV street lights but no 1960s ones. There are some places where only late 1970s-present cobras with NEMA tags are used but are MV. And, some cities were dominated by incandescent for a while, and they used mercury vapor as the upgrade up to the 2000s in some cases. Also, some places just wanted to modernize the look of their street lights without upgrading the light source. They did the same with HPS in the late 2010s and early 2020s in some cases where they used HPS spot replacements to replace older HPS fixtures (because an LED wouldn’t clash well), but now they just use LED anyway. Some cities used MH/PSMH as spot replacements for MV after MV was banned and they didn’t want HPS. Duke Energy was especially known to install MH street lights, which is why they are seen in Greenville or Charleston, SC. They were less common as new installs but some places did actually use them as new installs if they wanted the white light of a mercury lamp and not the orange color of high pressure sodium, without the drawbacks of metal halide (shorter lifespan, potential risk of explosion, poor lumen maintenance, color shifting), which is why you may occasionally see a subdivision or neighborhood from the 2000s with MV cobra heads or post tops. If you go to a city, town, or village dominated by MV, you’ll likely find a 2000s MV fixture somewhere (whether a NEMA head, cobra head, or a coach style lantern). In HPS dominated cities, towns, or villages they’re pretty much non existent in most cases, with the exceptions of miss-outs of fixtures usually from the 80s or prior. Mercury vapor was still much more common than metal halide (outside of private property and special applications) in the 2000s. Metal halide was way more than common for any private commercial property, and MH shoeboxes became very prominent (just as common as the HPS ones, if not more). Metal halide also was way more common than mercury vapor for wall packs, indoor lighting, canopy lights, stadium lighting, and recessed HID lights. Most roads lit with shoeboxes used the HPS versions (it is quite uncommon to find MH shoeboxes as street lights instead of parking lot lights). Cities didn’t want to keep replacing metal halide bulbs so they just went with MV if they wanted a white light, if they wanted efficiency, they went with HPS, if they wanted white light, they went with MV (this was standard for installations between the late 1970s and 2008). The only benefit of metal halide vs mercury vapor was higher efficiency than MV and better light quality. Other than that, MV was superior. No, MH lamps do not emit less UV light than mercury vapor. A clear mercury vapor and a clear metal halide lamp I believe actually emits similar levels of UV light, despite them being a different color and putting out a different type of light. There is no research that suggests that metal halide bulbs produce less ultraviolet light than mercury vapor bulbs. In fact, a coated mercury lamp would likely produce less UV than a clear metal halide lamp.
MH cobra heads are very rare in wattages under 175 watts (even for PSMH). Most MH street lights installed before 2009 are probe start. PSMH street lights installed before 2009 are extremely rare (with exceptions for acorns with lower wattage MH lamps). Most manufacturers didn’t even make PSMH cobra heads until 2008 or 2009. They did for like high bays, shoeboxes, or wall packs, but probe start was more common for pretty much anything in the 2000s. Even the 90s or 2000s shoeboxes, low bays, wall packs, canopy lights, or high bays you see are usually probe start. MH cobra heads usually were used as replacements for MV cobras (usually as spot replacements but sometimes as an upgrade).
I'd expect a bit more with their price tag!