FWIW; by now everybody has figured out my screen name. I'm not complaining, bragging or bitching about the state of pyro here. All I gotta offer is a couple of obs;
1) Drones are user friendly and replacing aerial displays at light speed. No pun intended.
2) PETA, et al, has championed and exposed ( maybe exaggerated, not my soap box) the deletorius effects on animals, with the ears of local politicians snd we all know how that goes.
3) Tradional construction techniques have evolved over the years ( natch!) and include more labour and cost- saving use of plastics. Naturally, this includes environmental impacts if the show sites are not cleaned commercially. Tradional paper snd glue, while unsightly, ultimately degrade or weather away, esp. in climates that include periodic precipitation. Not so much in the Southwest. Cost factors always drive a show contract with the founding fathers, marketing folks, advertisers, or the collection of mouth breathers at City Hall. Plastic is cheaper, by a ton, due to the rapidity with which the poor wage slaves can fill shipping containers in India and China ( mostly). Conditions are brutal and depressing to see, given the repetitive, non-machine based construction techniques that have to be employed in like, shot cakes. Shells are a completely diffent ball of wax (again no pun intended). Yes, there is some automatiom, like quick match and fuse that have benifitted by this.
4) The evolution from nail boards to slaved, computer driven shows incorporating audio, have pushed the ability to colour the sky to denser shows and upped the expectations of viewers. More product and even more 'designers' to choreograph said shots. For those in the west, we pioneered the laser shows ripped off from the gels snd oil frame projections from the 'love-in' dance floor generation into the sky. We were busted by the FAA for the first KGB ( a radio station) Sky Show practice/demo? before it was really accepted and Notams became regular.
So, lazers, animal rights, the husband and wife team that developed the AI drone tech for formation flying, the costs of EPA, snd a few other zillion reasons, have lead to the steadily decreasing black powder based shows. Thus the increasing ( in parts as described) costs associated with them.
Sorry, prolly more that any body cares about, but my random 2 cents. Above all, stay safe out there and have a great 4th! I am, because I get to stay home with my sweetie! And maybe work on a rocket!