The city I live in has gone to all LED traffic signal lights. Twenty-two years ago there were only three signal light controlled intersections with the city limits. There were also only about 22K people. Now nearing 80K people and I lost track of the numbers of signal lights a decade ago.
The LED lights not only save electrical power (up to 90% less than a conventional signal set) but it also has greatly reduced the maintenance costs.
Because my dad is in the hospital there, I've been going over to the small city of Wenatchee, WA a lot lately. In an older area of town they have the adorable old stoplights from my childhood. The kind that were in Dick and Jane readers - colored glass lenses with visors over the top and little square glass panels with instructions in way too small a type for today such as "No Right Turn".
I'm sure the incandescent bulbs in these lights require constant maintenance. Two or three years or so of maintenance would probably buy the newer LED traffic lights.
They can sell them on Ebay, or keep them to rent out to movie companies doing things set in 60 or so years ago.
Be a shame to just throw them away, though.
(not including a couple of school areas, this county has three stop lights. I expect that will change after a bit.)