I recall when suspended ceilings were the cats' meow of ceilings. The neatest thing about them was the wide-open nature of the area above the grid, that allowed you to easily shift lights about as needed.
They were also a good, easy way to conceal or even out a messed-up, cluttered ceiling. No more looking at the plumbing or I-beams. Helped alot with noise from the typing pool too.
Then everyone started packing stuff into the ceiling. Data/phone guys started draping tons of wire over the fixtures.
A litte earthquake gave us some dramatic footage of such a ceiling floundering about like a fish on deck, before disintegrating before our eyes. The dust settles, and there were all the fixtures swinging from their whips.
That the ceiling in question was probably not installed correctly was something never discussed. Instead, 'earthquake' codes quickly mandated all manner of additional supports - additionl ones for the hacks to 'forget,' just like the missing wires in that failed ceiling.
Add to that confusion regarding fire-rated ceiling assemblies. That Caddy made - and probably continues to make - an entire line of electrical supports designed to attach your stuff to the grid is forgotten.
Look above such a ceiling today, and there's hardly room for a mouse ... then, have fun getting that tile back in place.
This all makes me wonder if the day of the suspended ceiling is past, and if they will go the way of Knob & Tube.
I doubt T bar will ever go away in commercial buildings. It is a cheap and effective way to deal with office space built in steel truss construction and easy to change when the floor plan changes. I agree it has fallen out of favor in residential. There was a lot of abuse of that space by IT techs, I was guilty of that myself. A lot of that got fixed when they bought us a taller ladder so we could string our CAT5 and coax through the steel trusses and not right on the grid
I still would bet there are non rated data cables and even orange extension cords running through most office ceilings.
Living in a seismic ares I have certainly seen a vast improvement of the suspension of both the grid and the luminaires installed there as well as a general improvement of the wiring in them. Still a lot of poorly supported wiring of all function but an improvement. I am seeing more new buildings that just spray everything black rather than build a t-bar cieling. Those cielings often have very good looking installations as it is out for everyone to see. T bar or the equivalent is here for a long time to come.
My first experience with the new-wave black-paint look was Century 25 Theatres in Union City California.
Too late to participate in the wire job...
I was thrown at salvaging the life safety contract: Fire Alarm!
I must say that the reason such was sellected was first cost and continuing costs.
Out there, some engineer exists who calculated that the building would shave 5% on its energy bill by not having a hot 'plenum' over the lobby. The thinking being that the tiles trap heat at elevated temperatures which frustrate HVAC distribution to the 25 sub-theatres... or some such.
I can't quite figure out how that is so... but I just build the place -- not design it.
The painters absolutely LOVED that job. The owner keep changing the paint scheme at the last second. Some walls have more coats than can believe.
Since that time the method has spread all over: Albertsons adopted it, so, too, Safeway. The grid crews are weeping.
Of course, Costco uses it.
I see two colors in wide use: very, very black & very, very white.
It does tend to drive the install towards EMT. The most common style seems to be EMT to 4-squares fitted with 'industrial covers' featuring twist-lock receptacles rated to 20A @277V. Then SOJ whips drop off to high-bays or SHO T5 fixtures on hooks or jack chain.
There are many efficiencies to be had: the contractor can split the task into fixture crews ( apprentices ) and EMT runners...
I don't see it going away for big box retailers.
As for ceiling tiles in retro-work: the demo is ALWAYS ultra nasty. I'm talking rodents and their leavings. Recommend full bio-protection for anyone forced into such duty. Definitely NOT for the asthmatic!