It's not as simple as that story makes it out to be.
I've seen some of the daftness locally, and spoken off the record to some of the officials involved. Here are a few thoughts:
The article does explain about conservation areas. If we want a nice built environment, one which keeps the better bits of older architecture, we have to maintain it somehow. The council is obligated both to do this and at the lowest practical cost.
The council has to replace street lighting. It is very difficult to refurbish lamp standards in situ, and anyway that's not necessarily helpful.
For example, although I am in a conservation area, our road is an important through-route:
It was long ago discovered that having street lighting high up is good for a number of reasons: it improves driver safety (in several ways) and it is better for dark skies. So, in a road once lit by gas in a similar way to the lamps we were discussing, we now have thirty or thirty-five foot tall standards, each with a LED array at the top. Even this doesn't "fix" every problem, as in the summer, trees in leaf shade the footpaths. But, because traffic apparently cannot cope otherwise, "daylght" is now 24x7. LEDs make it affordable, but it isn't nice in the daytime (looks industrial). That said, as a resident, I think the street lighting is better than it was - less eye strain when outside at night, etc.
But the two streets adjacent to my bit of our road have "traditional" standards. Actually they don't. The cast-iron originals had sunk-in to an unwanted extra depth of about two feet, so the decorative moulding round the base was at pavement level. They couldn't even be rewired without a lot of work. Instead they now have modern, heavily galvanized standards, with an authentic plastic sleeve over the top, to add fluting and style. I believe it's paintable, too, although ours are black presently.
Everybody wins, except that, for some totally daft reason, the new ones have been moved to the outside edge of the pavement, so that they interfere with the progress of blind and disabled people, and with car doors, etc., when parking.
The old standards were taken away for refurbishment where possible (and then for stock). If you know Clifton, mentioned in the piece, you'll also know it's been used for many period TV and film dramas, and it is a lovely area (like central Bath but on a smaller scale).
Although our gaslight-era standards were taken, I want salvageable old fittings to go to Clifton and similar areas: 30-foot LED standards would look horrible. Anyway, I'm sure you know of the joys of welding cast iron too - many of the standards removed from here will not be suitable for re-use anyway - I'd guess fewer than 20%.
So whatever that silly web site says, the situation is a lot more nuanced. The council has its priorities (such as social services) given to it by central government (by laws), and pretty street lamps are way, way down that list. I criticise them for many things, but in the case of street lighting, I think they are doing pretty well considering.